KTN, which said four people were feared killed on Wednesday, said the youth later died. Police spokesman Eric Kiraithe told media those shot in Kisumu had attacked officers first.
'TWO BULLS FIGHT'
Also on Wednesday, TV footage showed police tear-gassing opposition leaders at two hotels, and then chasing them down Nairobi's main Kenyatta Avenue. Odinga was near but stayed in his four-wheel drive truck, the footage showed.
Human Rights Watch said police have been heavy-handed and have killed at least 47 people during the post-election turmoil.
Around 620 have been killed nationwide in attacks on tribes and people suspected of having supported Kibaki, and by police.
A quarter of a million people, many of them members of Kibaki's Kikuyu ethnic group, have been forced from their homes.
International observers have said the vote fell short of democratic standards and both sides accuse the other of rigging.
The United States and former colonial power Britain have called on Kibaki's government to let peaceful protests go ahead.
They and 11 other nations have threatened to cut aid if the government's commitment to "good governance, democracy, the rule of law and human rights weakens".
But those are likely empty threats because Kenya gets less than 5 percent of its budget from donors.
The Nation newspaper urged both sides to "isolate dangerous demagogues" in their midst to forge a compromise to save Kenya.
"When two bulls fight ... it is the grass that suffers. The grass here is the ordinary people of Kenya who have been reduced to expendable cannon fodder as the rich and powerful duel for political supremacy," the paper said in an editorial.
Since being sworn in, Kibaki, 76, has entrenched his position by naming most of a new cabinet, including figures the ODM says are hardliners, and calling parliament to meet.
Former U.N. boss Kofi Annan had been due in Kenya this week to lead a team of "Eminent Africans" in a push for peace, but he fell ill. His office gave no date for his arrival.
