One of Nigeria's most senior policemen has died in a helicopter crash in the central city of Jos, police have said.
John Haruna, a deputy inspector general of police, was among four police personnel who were killed.
They were on a routine aerial patrol of Jos and the cause of the crash is not yet known.
Police are part of a special task force to contain inter-communal conflict in Jos, which has also been targeted by Islamist Boko Haram militants lately.
Jos is the capital of Plateau state, which lies on the fault line between Nigeria's mainly Muslim north and Christian and animist south.
Poor air safety
Witnesses said the aircraft burst into flames when it crashed in the residential suburb of Rukuba.
Yushau Shuaib, the national spokesman for Nigeria's National Emergency Management Agency, says the helicopter crashed into homes, but no-one else was hurt, the AP news agency reports.
Nigeria, like many African countries, has a poor air safety record, though some efforts have been made to improve it since a spate of airline disasters in 2005.
On Tuesday, in Abuja there was a complete shutdown of operations at the capital's international airport, following a power surge that damaged lights on the runway.