Today marks International Blasphemy Day – designed to encourage people to speak out against repressive laws that forbid the criticism of religion.
Around a quarter of the world's countries have blasphemy laws, and more than a tenth penalise apostasy – the renunciation of religious belief. Breaking these laws can result in harsh punishments, and even death in some cases.
An annual report on religious freedom released by the US State Department in August said that one of its main concerns with regards to religious liberty is blasphemy and apostasy laws, which it said "conflict with and undermine universally recognized human rights".
In many Islamic societies, "societal passions associated with blasphemy – deadly enough in and of themselves – are abetted by a legal code that harshly penalizes blasphemy and apostasy," the report said.
"All residents of countries where laws or social norms encourage the death penalty for blasphemy are vulnerable to attacks... This is particularly true for those who have less power and are more vulnerable in those societies, like women, religious minorities, and the poor."
It highlighted the issue of false accusations, "often lodged in pursuit of personal vendettas or for the personal gain of the accuser", and said mob violence as a result of these accusations is "disturbingly common".
Courts which hand down punishments for blasphemy "severely curtail the religious freedom of their residents," the report warned.
Here are four recent cases of Christians suffering as a result of repressive blasphemy laws around the world.
Asia Bibi in Pakistan
Christian mother-of-five Asia Bibi has been on death row since 2010, after being accused by her former colleagues of blaspheming against the Prophet Mohammad – a charge she denies.
She was last year reportedly put in solitary confinement in her prison in Multan, eastern Pakistan, over fears she may be attacked by vigilantes. Persecution charity Release International has warned that one Muslim cleric has offered 500,000 rupees – about £4,000 – to anyone who manages to kill her.
Bibi will next month face an appeals court, and campaigners have set up a petition urging Pakistan's Prime Minister Nawaz Sharif to abolish the "iniquitous" blasphemy laws.
At least 95 per cent of the Pakistani population is Muslim, and Islam is enshrined in the constitution as the state religion. The US Commission for International Religious Freedom (USCIRF) last year said the country represented "one of the worst situations in the world for religious freedom" and accused the Pakistani government of failing to provide adequate protections for faiths other than Islam. It argued that repressive blasphemy laws in particular are used to target religious minorities.
These laws prescribe life imprisonment for the desecration of the Qur'an and the death sentence for "defiling" the Prophet Mohammad, and accusations of incidents have often prompted mob violence. According to the Centre for Research and Security Studied in Pakistan, more than 62 people have been killed in such incidents since 1990. More than 40 people are currently on death row for blasphemy, the majority of whom are members of religious minorities.
Slimane Bouhafs in Algeria
An Algerian court this month sentenced 49-year-old Slimane Bouhafs to three years in jail for "insulting Islam" in a series of Facebook posts.
He had previously been charged with blasphemy and given five years in jail – the maximum punishment – but this was reduced by an appeals court.
The court's judgement said Bouhafs had "shared four distorted Koranic verses and photos offensive to the Prophet, as well as articles denigrating the Islamic religion," and that his conviction was on the basis of a series of online posts between May and June 2016.
These included "a caricature representing the Prophet Mohamed as a terrorist" and other posts "slandering Islam as a religion of intolerance and hatred."
Human Rights Watch said Bouhafs had shared on Facebook an open letter he had written to the secretary general of the UN, in which he denounced the "Islamisation of Algerian society" and the repression of Ahmadi Muslims and Christians.
There are just 39,000 Christians among Algeria's population of more than 40 million, which is predominantly Muslim. The country ranks 37th on persecution charity Open Doors' list of places where it is most dangerous to be a Christian, and the charity has said the government is coming under increasing pressure to implement more Islamic legislation by Islamist groups.
Conversion from Islam (or an attempt to convert someone else) is illegal and Muslim converts are forced to worship in secret. Only Muslims may hold public assembly and churches are often denied registration.
Four Coptic Christian teenagers in Egypt
Four Coptic Christian Egyptian teenage boys are now seeking asylum in Switzerland after being convicted of blasphemy by a court in Minya in February this year.
Mueller Edward, 17, Bassem Hanna, 16, and Alber Ashraf, 16, were sentenced to five years in prison, while Clinton Yousef, who at the time was aged 15, was placed in a juvenile facility.
They were charged with blasphemy after being filmed by their teacher pretending to pray while reciting verses from the Qur'an in January 2015. The students are shown in the video laughing and one appears to pretend to slit the throat of another, apparently mocking ISIS-style beheadings.
They were sentenced for "contempt of Islam and inciting sectarian strife".
However, they were later released and allowed to travel to Turkey, where they sought a humanitarian visa to Switzerland. Their teacher, Gad Younan, was sentenced to three years in prison in December 2015, and was expelled from his village.
The Egyptian penal code forbids citizens from "ridiculing or insulting heavenly religions or inciting sectarian strife". According to the USCIRF, this law is used to "detain, prosecute, and imprison members of religious groups whose practices deviate from mainstream Islamic beliefs".
Blasphemy cases in Egypt have risen since the revolution in 2011, and the majority of those sentenced to jail have been Christians, Shi'a Muslims and atheists.
Bridget Agbahime in Nigeria
An elderly pastor's wife, Bridget Agbahime was beaten to death by an angry mob in June following allegations that she had blasphemed.
The 74-year-old was accused by a fellow shop owner on June 2, and a mob of 500 soon gathered. According to Christian Solidarity Worldwide (CSW), a Muslim trader tried to hide Agbahime and her husband inside her shop, but the mob broke in and beat her to death in front of her husband.
A local lawyer told CSW that the allegation of blasphemy was "a pure lie... She [Agbahime] was killed because of envy over a shop".
Nigeria has two parallel court systems, Customary and Sharia, both of which forbid blasphemy.
Open Doors has ranked Nigeria as one of the most dangerous places in the world to be a Christian, and blasphemy accusations are believed to be on the rise in the country.