Safia Sediqi, a representative for eastern Nangarhar province and an adviser to the rural development minister, said she escaped an attempted ambush on Monday as she was travelling to the provincial capital Jalalabad.
"I was on my way back from Khogiani district to Jalabad city when we saw two armed men on the highway waiting for our convoy, but as soon as they realised we had more than a dozen bodyguards they tried to escape," she said.
Sediqi said her guards gave chase, but one attacker escaped while the other committed suicide as they were trying to arrest him.
ID card destroyed
The attacker who killed himself, "swallowed his identity card and destroyed documents he had on him, then he blew himself with one of the hand grenade he was carrying," she said.
The attack is the latest incident in a wave of violence which has swept the country in the run-up to the presidential elections now scheduled for 9 October.
Sediqi was on a mission to Nangarhar to look at rural problems and went to Khogiani district some 90km east of the capital Kabul to investigate the drinking water shortage in the district.
"...as soon as they realised we had more than a dozen bodyguards they tried to escape"
Khogiani district has been the scene of violent attacks on electoral workers. Four women working for the elections board were killed there and more than a dozen others injured in recent weeks.
Abd al-Wakeel Ataak, spokesman for the provincial governor, confirmed the details and said authorities had thwarted other attacks in the area.
US soldier dies
Meanwhile, a US soldier died of a non-combat related injury at Bagram Air Base north of the Afghan capital Kabul on Monday, the US military said in a statement.
The military was investigating the cause of death, the statement added.
The latest death brings to 132 the number of coalition troops who have died in Afghanistan since late 2001 when the US invaded the country.
In the past two months more than 10 members of the US-led coalition have been killed in Afghanistan.