MOSCOW (AP) _ A strong earthquake hit Soviet Georgia on Monday, setting off rockslides in mountain villages and killing at least 40 people, authorities said.

The quake also was felt in neighboring Armenia, which was devastated by a 1988 earthquake that killed 25,000 people. There were no reports of damage or injuries in Armenia.

Police spokesman Zurab Kadzhaya in the Georgian town of Kutaisi, near the epicenter, said Monday night about 40 people were killed and buildings in five mountain towns suffered widespread damage. The official Tass news agency earlier reported 30 people killed. It was not immediately known how many people were injured.

There were fears the death toll could rise as rescuers searched collapsed buildings in villages isolated by severed communications.

An aftershock as powerful as the initial quake struck the region at 9:33 p.m. (2:33 p.m. EDT), Tass said. U.S. Geological Survey spokeswoman Pat Jorgenson in Menlo Park, Calif., said the aftershock registered 6.2 on the Richter Scale.

Soviet Interior Ministry troops already in the region to quell ethnic unrest were ordered to the disaster area to aid in rescue efforts.

The initial quake struck at 12:13 p.m. (5:13 a.m. EDT) in north-central Georgia among the sparsely populated villages and towns in the Caucasus Mountains. It measured 7.1 on the Richter scale, according to the Soviet Union's Central Seismic Station.

The epicenter was near Dzhava, a town of 11,000 people about 60 miles northwest of the Georgian capital of Tbilisi.

In a report from Dzhava, Soviet TV showed collapsed buildings and others with gaping holes. Rescuers standing atop a mound of rubble dug frantically with their hands to remove large stones in search of further victims.

The independent Interfax news agency said a kindergarten, a high school, a hospital and a printing house were among buildings destroyed there, in addition to 30 homes.

The evening TV program ''Vremya'' showed rescuers pulling an injured woman from a badly damaged building in Dzhava. Another woman sat stunned outside a shattered house with her arm in a sling.

Don Finley of the U.S. Geological Survey in Reston, Va., put the Richter reading at 7.2 and said the quake released about four times as much energy as the 1988 Armenian quake.

Kadzhaya said by telephone from Kutaisi, 63 miles west of Dzhava, that about 40 people were killed in the region Monday and about 80 percent of the buildings were destroyed in Dzhava, Ambrolauri, Onei, Chiatura and Sachkhere.

''It was terrible, really terrible,'' Marina Ivanova, a pediatrician in Tbilisi, said by telephone.

''The building was shaking like a house of cards. We grabbed our children and rushed downstairs.''

She said other residents of her building also fled, but that damage appeared to be limited to cracked walls.

Aftershocks continued throughout the day in the region, and a ''Vremya'' camera even captured one strong aftershock collapsing an already severely damaged building.

Electricity and water supplies were disrupted in Dzhava and communications were severed, ''Vremya'' correspondent A. Parfendkov reported.

''Dzhava is awaiting help,'' he said.

Other reports said rocks cascaded off a mountainside onto houses in Chiatura and a railroad station was badly damaged in Sachkhere, Georgian officials in Moscow said.

''The mountain fell onto the houses,'' said Marina Starostina, a Georgian government spokeswoman in Moscow.

Georgian Prime Minister Tengiz Sigua led a government commission to the scene, and the Soviet government expressed condolences to bereaved families.

Shakro Dekanoidze, a police officer in Kutaisi, said two helicopters were sent to survey damage.

Tass said the quake was felt for 30 seconds in Yerevan, the Armenian capital. It also was felt in Spitak, an Armenian town that was flattened by the Dec. 7, 1988, quake.

That earthquake, which was calculated at 6.9 on the Richter scale, leveled hundreds of apartment buildings and trapped tens of thousands of people under tons of rubble. About 500,000 people were left homeless.

Jorgenson suggested the relatively light population of the hardest-hit areas Monday might account for the smaller amount of damage.

The American Red Cross in Washington reported Monday the League of Red Cross and Red Crescent Societies has sent an assessment team to Georgia. It said the Armenian Red Cross also has sent a 27-member rescue team.

The Richter scale is a gauge of the energy released by an earthquake, as measured by the ground motion recorded on a seismograph. A quake with a magnitude of 6 can cause severe damage. A quake measuring 7 is capable of causing heavy, widespread damage.

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