L'AQUILA, Italy - A powerful earthquake struck central Italy early Monday, killing more than 100 people, making up to 50,000 homeless and flattening entire medieval towns while residents slept.

As rescue workers combed through the rubble for survivors and rushed to set up tents for the homeless before night fell, officials warned the death toll could still rise substantially and declined to estimate the number of missing.

Most of the dead were in L'Aquila, a 13th century mountain city about 100 km (60 miles) east of Rome, and surrounding towns and villages in the Abruzzo region.

Some towns in the area have been virtually destroyed in their entirety, said Gianfranco Fini, speaker of the lower house of parliament, as MPs observed a moment of silence.

Abruzzo's regional government said more than 100 people were confirmed dead, nearly 14 hours after the quake struck with a magnitude of between 5.8 and 6.3.

I woke up hearing what sounded like a bomb, said L'Aquila resident Angela Palumbo, 87.

We managed to escape with things falling all around us. Everything was shaking, furniture falling. I don't remember ever seeing anything like this in my life.

Prime Minister Silvio Berlusconi canceled a trip to Moscow and declared a national emergency, freeing up funds for aid and rebuilding. But he also appeared on the defensive about reports that officials shrugged off a warning about the quake weeks ago.

Flying in to the disaster zone, Berlusconi told reporters that now was the time to concentrate on relief efforts and we can discuss afterwards about the predictability of earthquakes.

Civil Protection Department officials said up to 50,000 people may have been made homeless in some 26 cities and towns. More than 1,500 people were injured and thousands of houses, churches and buildings collapsed or were damaged.

Rubble was strewn throughout L'Aquila, a city of 68,000, and nearby towns, blocking roads and hampering rescue teams. Old women wailed and residents armed with only their bare hands helped firefighters and rescue workers tear through the rubble.

In the small town of Onna, 10 people were killed, said a Reuters photographer who saw a mother and her infant daughter carried away in the same coffin.

Older houses and buildings made of stone, particularly in outlying villages that have not seen much restoration, collapsed like straw houses.

Hospitals appealed for help from doctors and nurses throughout Italy. The smell of gas filled parts of the mountain towns and villages, pouring out of ruptured mains.

Berlusconi told reporters in L'Aquila that tent cities and field hospitals would be set up there and hotels on the Adriatic coast would be requisitioned to shelter the homeless.

We're hoping they give us a tent or something to sleep under tonight, said 70-year-old Isenia Santilli, taking shelter at a sports field outside L'Aquila's city center where the Red Cross was feeding quake victims.

Residents of Rome, which is rarely hit by seismic activity, were woken by the quake, which rattled furniture and swayed lights in most of central Italy. It struck shortly after 3:30 a.m. (0130 GMT).

Pope Benedict said he was saying a special prayer for the victims.

MY FATHER IS SURELY DEAD

When the quake hit, I rushed out to my father's house and opened the main door and everything had collapsed. My father is surely dead. I called for help but no one was around, said Camillo Berardi in L'Aquila.

A resident standing by an apartment block that was reduced to the height of an adult said: This building was four storeys high.

In another part of the city, residents tried to hush the wailing of grief to try to pinpoint the sound of a crying baby.

Part of a university residence and a hotel collapsed in L'Aquila and at least one person was still trapped.

At least four Romanesque and Renaissance churches and a 16th century castle were damaged, the Culture Ministry said.

Part of the nave of the Basilica of Santa Maria di Collemaggio, one of the area's best-known churches, collapsed. To the north, the belltower of the lavish Renaissance Basilica of San Bernardino also crumbled.

Bridges and highways in the mountainous area were closed as a precaution.

Weeks before the disaster, an Italian scientist had predicted a major quake around L'Aquila, based on concentrations of radon gas found around seismically active areas.

Seismologist Gioacchino Giuliani, who lives in L'Aquila, was reported to police for spreading alarm and was forced to remove his findings from the Internet.

Civil Protection assured locals at the end of March that tremors being felt were absolutely normal for a seismic area.

Earthquakes can be particularly dangerous in parts of Italy because so many buildings are centuries old. About 2,700 people died in an earthquake in the south in 1980.