ARMENIA, Colombia (Reuters) - Colombia`s President Andres Pastrana ordered a military crackdown in this earthquake-torn city on Thursday after a day of looting and rioting by survivors of the tremor that killed at least 883 people. Pastrana, who flew into Armenia on Wednesday night vowing to impose order and speed up relief to about 250,000 people left homeless by the quake, said 2,000 soldiers and 700 policeman would be brought in to stamp out gangs of armed looters still roaming the streets. Monday`s quake, measuring 6.0 on the Richter scale, created a disaster zone that covered 20 towns and villages across five provinces in Colombia`s central coffee-region. Armenia, a city of 280,000 people, bore the brunt of the destruction. Frayed tempers boiled over on Wednesday as survivors, tired of waiting for government aid to arrive, took matters into their own hands, smashing their way into scores of downtown stores and businesses to carry off food and water as well as shoes, jewelry and compact discs. What started as an isolated incident quickly degenerated as crowds of hundreds swelled into thousands in a rampage that engulfed the entire downtown area. Some residents threw rocks at police, who responded by firing bursts of automatic gunfire into the air. Television images showed similar scenes in the neighbouring town of Calarca where nightstick-wielding police made half-hearted attempts to stop scores of people stripping the shelves of a local supermarket bare. The looting continued even as aftershocks rattled the crumbling buildings. As night fell fearful locals set up well-armed neighbourhood vigilante squads to fend off further raids. The vigilante groups, which gathered on street corners around campfires, were armed with an array of machetes, shotguns, pistols and even Molotov cocktails. While security officials deplored the violence, they acknowledged that the disturbances were fuelled by hunger and desperation. Speaking to reporters at Armenia airport late on Wednesday, Pastrana said he had arrived to personally take charge of the relief operation and would stay in the city for about three days. Despite a massive response both in Colombia and abroad to appeals for aid for survivors, virtually none has reached Armenia, where many families spent a third night huddled under improvised shelters in front of their ruined homes. Government officials were unable to explain why most of the 95 tons of relief aid still remained on the tarmac of Armenia`s airport late on Wednesday. Amid the chaotic scenes on the streets, the slow search for survivors continued. Spirits were briefly lifted early in the day when two teenage boys were pulled alive from the ruins where they had been trapped for more than 40 hours. But rescue workers, who used their bare hands to haul aside the rubble, said the latest figures from the Red Cross - 883 killed and 3,626 injured - was low and would go far higher.