At least 20 people have been killed and 100 others wounded after a suicide bomber blew up a truck at a local police station in Russia's volatile North Caucasus region.

Policemen work at the site of explosion in a police compound in Nazran, 17 Aug 2009

Police say the bomber detonated a truck packed full of explosives in Nazran, the capital of Ingushetia. The bomb exploded at the gate of the local police headquarters just as officers were lining up for work early Monday.

Ingushetia's Interior Ministry Spokeswoman Marina Hajiva described the scene to Russian television speaking through an interpreter.

"Rescue workers are going [to] the site of the terrorist attack in Nazran. Investigation and fire crews are operating at the scene. Let me remind you that at nine this morning someone drove a vehicle stuffed with explosives through the gates of the Nazran region internal affairs building. This caused an explosion and fire," Hajiva said.

The blast also triggered a fire in a weapons room and ammunition was detonated. Witnesses say that the explosion could be heard throughout the city. The bombing is the latest in a string of deadly attacks in Russia's volatile North Caucus region.

Last week, Ingushetia's construction minister was shot to death in his own office. He had been investigating construction fraud throughout the region. In June, Ingushetia's president was severely wounded in a suicide car bomb attack and a supreme court justice was killed after dropping her children off at school.

Russian President Dmitry Medvedev says Moscow will take additional measures to ensure security in the region, which borders Chechnya. Officials blame the violence on Islamic militants and separatist groups.