BAQUBA, Iraq (Reuters) - A suicide bomber in northern Iraq blew himself up at a funeral procession on Sunday, killing at least 10 people and wounding 25, as the country suffers its worst spate of violence for at least five years.
No group claimed responsibility for Sunday's attack but suicide bombers linked to al Qaeda frequently target local Sunni Muslim leaders and followers considered supportive of Iraq's Shi'ite-led government.
The bombing took place in Muqdadya, 80 km (50 miles) northeast of Baghdad, among mourners in a cemetery. They were escorting the body of a prominent Sunni tribal sheikh, Mudhher Ali al-Shalal, who was killed on Saturday by unknown gunmen.
"As we were heading to the grave, a stranger ran towards the crowd and blew himself up," said Firas Ahmed, a relative of the deceased who was wounded in the leg.
"I was lucky because I was not at the front. The bodies of the killed and wounded people were everywhere."
Shalal was the son of another well-established tribal sheikh. His father had set up a local government-backed Sunni Sahwa militia opposed to al Qaeda.
This year has been Iraq's most violent since 2006-7, when tens of thousands died in strife between Sunnis and Shi'ites.
The government blames groups mainly linked to the Iraqi wing of al Qaeda and says the violence has been stirred by the civil war in neighboring Syria, which pits Sunni rebels against a government allied to Shi'ite Iran.
Hundreds of Iraqis were killed last month, figures from the United Nations and the Iraqi government showed on Sunday.
"I am profoundly disturbed by the recent surge in execution-style killings that have been carried out in a particularly horrendous and unspeakable manner," U.N. envoy Nickolay Mladenov said in a statement.
On Friday police discovered the bodies of 18 men, including a Sunni tribal sheikh and his son, who had been abducted and shot in the head near Baghdad in an attack a senior security official said bore the hallmarks of al Qaeda.
It was the deadliest in a series of assassinations last week, which also included an attack on Sunni laborers whose beheaded bodies were dumped in an orchard.
Mladenov called on the Iraqi government to track down all of the attackers "as a matter of urgency".
Iraqi security officials and analysts say the violence has more to do with insurgents trying to destabilize the government, and with infighting within sects, than with hostility between Sunni and Shi'ite communities. But they warn that such chaos could set off wider sectarian violence.
Last month 659 Iraqis were killed, Mladenov's office said. Iraq's Interior Ministry put the figure at 1,121 people killed.
Estimates from the two offices often vary. Both said around 1,300 people had been wounded in November.
In a separate incident on Sunday gunmen shot dead another Sunni sheikh, Khalid Hammoud al-Jumaili, and his driver, police said. Jumaili was a leader of anti-government demonstrations in Falluja which erupted in December last year across Iraq's western provinces.
(Reporting by a Reuters reporter in Baquba, Sylvia Westall and Suadad al-Salhy; editing by Andrew Roche)