Kabul, January 23:

A bomber blew himself up in a crowd of workers outside a US military base in eastern Afghanistan today, killing as many as 10 people in the deadliest suicide attack in four months, officials said.

The attacker, who also died, triggered explosives strapped to his chest among the workers as they lined up outside the base in Khost, said Jamal Arsalah, the governor of Khost province.

Arsalah said 10 men were killed and 14 injured. However, the NATO-led force that includes the US base said eight Afghans, including two policemen, were killed and five others wounded. It was not clear why the tallies differed.

Maj Matt Hackathorn, a US military spokesman, said there was no word of any US military casualties.

The governor said the bomber struck just as hundreds of Afghan workers waited to enter the base, known as Camp Salerno, through its main gate. He said concrete barriers, which protect the base and restrict access to the gate, had helped prevent a heavier toll.

The NATO-led International Security Assistance Force said the attacker detonated an explosives-filled vest when he reached the point where people entering the base are searched.