|TOP|Pope Benedict XVI has expressed his heartfelt sorrow over the killing of a Catholic priest in Turkey.

Officials in Turkey suspect that the killing of Catholic priest Andrea Santaro on Sunday is the work of a lone gunman although they have not ruled out the possibility of links to the outrage still widespread in the global Muslim community over controversial cartoons of the Prophet Mohammad.

A police sketch has been released of the gunman who shot Santaro at the weekend as he prayed in his church in the city of Trabzon on the Black Sea.

Turkey’s Foreign Minister, Abdullah Gul told reporters: "We strongly condemn this incident... We believe it is the work of one individual. His motive should become clear in due course.”

|QUOTE|A spokesman for the Vatican embassy in Turkey’s capital Ankara quoted eyewitness reports that the gunman, believed to be only 16 or 17 years old, shouted “Allahu Akbar” – Arabic for “God is greatest”, a common Muslim chant – as he shot Father Santaro dead, reports Reuters.

Pope Benedict expressed his deep-felt regret for the death of Santoro.

"I share the pain of the entire Church of Rome for the grave loss of such an esteemed and conscientious priest," the Pope said in a statement. "I hope that his spilt blood becomes a seed of hope to build an authentic brotherhood between people."

The Vatican, in a statement released at the weekend, also condemned the publication of the cartoons in several European newspapers and news websites.

The statement read: “The freedom of thought and expression, confirmed in the Declaration of Human Rights, can not include the right to offend religious feelings of the faithful. That principle obviously applies to any religion."

|AD|Turkey’s Prime Minister Tayyip Erdogan linked the shooting with the anger still strongly felt in the Muslim world over cartoons of the Prophet Mohammad first published in a Danish newspaper, saying both could be regarded as examples of intolerance.

"(The shooting) is extremely regrettable, especially after the recent developments in Denmark," NTV commercial television quoted Erdogan as saying.

"Above all, nothing about entering a place of worship to kill a priest is acceptable," he said.

Turkey, with a population of about 68 million, is overwhelmingly Muslim and has a tiny Christian population.

Despite this, violent attacks on Christian clergy are extremely uncommon in the country which regards itself as the bridge between the predominantly Muslim Middle East and Christian Europe.

The police have arrested a high school student suspected of the killing, according to Turkish news agency Anatolia, although police have yet to verify this report.

According to the Associated Press, a letter by Santaro dated Feb. 11th 2005 was reprinted in the Vatican newspaper, L’Osservatore Romano, in which the priest wrote to the missionary centre of the Rome diocese speaking of the need to exchange the “spiritual gifts” between East and West.

Father Santaro also mentioned, however, of an “emptiness” in the Middle East that needed to be filled with Christ.

A funeral for Santaro is being planned to take place in Rome’s main basilica, St. John Lateran, according to Italian news reports.