Moscow, Mar 15 (IANS/RIA Novosti): Police in Russia rescued several hostages held at a college in the southern city of Astrakhan and detained the hostage-taker who claimed to have a bomb, the interior ministry said.

Four people, including two young girls, were held hostage at the Volga-Caspian marine fishing industry college by a man claiming to be armed with a bomb, the ministry and the Investigative Committee said.

One hostage was later released by the man.

"During a special operation, the other hostages were set free and the man who had held them hostage was detained. The hostages were unharmed," the ministry said.

Along with the hostage-taker, police also detained his girlfriend who is a student of the college where the incident occurred.

The ministry previously said a security guard, two college teachers and two students were the five hostages.

The man who had seized them claimed a box he was holding contained explosives, but police later said they found no weapons or explosives, the ministry said.

"After police released the hostages and detained the suspect, they started to inspect the box, which the man claimed contained explosives. It turned out that there was a dummy in the box while the pistol seized from the man was a toy," the ministry said.

The hostage-taker had urgently demanded pizza be delivered to him during the siege, a police source said.

There was no information about the motive for the crime or any other demands from the hostage-taker.