BAGHDAD (Reuters/AFP) - At least five Iranians were killed on Wednesday when gunmen opened fire on a convoy of buses of religious pilgrims visiting holy sites in Iraq, police in Diyala province said. The attack took place on a highway connecting the Iranian border to Baghdad and southern Iraq, 45km northeast of the provincial capital Baquba, a police official said. He said five pilgrims were killed, including one woman, and 35 others were wounded. Iranian media said six people were killed and 31 wounded. In Iran, a state broadcasting website reported that Foreign Ministry spokesman Hassan Qashqavi condemned Wednesdays attack as a terrorist act and against divine and human values. The outcome of (US) occupation is still providing grounds for terrorists to continue their criminal acts, Qashqavi was quoted as saying. Meanwhile, American troops shot dead two "attackers" who tried to blast their convoy with hand grenades near Abu Ghraib west of Baghdad, the US military said on Wednesday. In addition, one civilian was killed and four wounded in Tuesdays incident, which also saw the convoy coming under small arms fire, said military spokesman Lt-Col Philip Smith. The convoy was on its way to an Iraqi police station in Abu Ghraib when two men attempted to throw hand grenades at it, Smith said. Soldiers positively identified the two men as (a) threat, engaged them with small arms fire, killing both of them, he said, adding that the incident was under investigation. Smith gave no further details on the killing and wounding of the civilians. As part of a security pact between Baghdad and Washington, the vast majority of US troops have left Iraqs urban areas ahead of a complete withdrawal from the country, due by the end of 2011. However, some American soldiers remain in Iraqi cities as trainers and advisors.