DUSHANBE (Reuters/AFP) - A bomb blew up a police car on Thursday evening in the Tajik capital Dushanbe where the presidents of Afghanistan, Pakistan and Russia were holding security talks, an interior ministry source said on Friday. Tajikistan, a volatile nation north of Afghanistan, was hosting a summit attended by Afghan President Hamid Karzai, Pakistans Asif Ali Zardari and Russias Dmitry Medvedev. The source said a bomb planted inside a police car went off, wounding one officer. No one was killed. We are trying to figure out whether it was a terrorist act or a personal grudge against this particular policeman, the source said. Medvedev was still in Tajikistan on Friday morning to attend a ceremony marking the opening of a Moscow-built hydroelectric power station outside the capital Dushanbe. Meanwhile, six members of Islamist Movement of Uzbekistan who allegedly received training in Pakistan were convicted in Tajikistan for belonging to a terrorist group, a court spokesman in the former Soviet republic said Friday. The conviction came as fears have mounted in Tajikistan over infiltration by militants from nearby Afghanistan and Pakistan. Tajikistans supreme court found these men - Tajik citizens - guilty of membership in a terrorist organisation and participation in a criminal group, a court spokesman told AFP. They belonged to the Islamist Movement of Uzbekistan (IMU) and received training in underground religious schools of Pakistan and were sent to Tajikistan, he added. The IMU - a religious group founded in 1998 to overthrow the government of Tajikistans neighbour Uzbekistan, and which later joined the Taliban - is considered a terrorist organisation by the US. Religious groups were largely pushed out of Tajikistan after the end of the countrys 1990s civil war, but in recent weeks signs have emerged that the fighters may be returning. On Wednesday, Tajik authorities said they had killed Nemat Azizov, a senior IMU member who had been suspected of trafficking narcotics to support groups in Afghanistan and Pakistan.