Last night I gazed out over a deserted city. After two days of deadly riots and arson attacks, the people of Lhasa hunkered down before a midnight deadline and a feared military crackdown.

Rubble and burnt-out vehicles littered the streets, but few people dared to set foot in the narrow and winding alleyways, fearful of turning a blind corner and running into an army patrol. Only the occasional gunshot rang out over the city, the whoops and cheers of the rioters silenced. Amid claims that many people have been killed in the most dramatic backlash against Chinese rule for almost 20 years, a showdown looms tonight. The rioters must turn themselves in by midnight or face the consequences.

Things began to look different, and much more frightening, late on Saturday. The troops armed with batons who were ringing the old Tibetan quarter began to carry rifles instead. Tibetans whom I had seen tossing stones at the troops earlier in the day (and getting tear-gassed in return; the gas stung my eyes as it wafted over the hotel) began to hold well back. One soldier turned his rifle on me as I stepped around the corner of an alleyway to get a better look.

By late afternoon the troops, members of the People’s Armed Police, were entering the alleyways themselves, firing the occasional shot. One appeared suddenly on the roof of my hotel where two Americans and a Tibetan crouched in terror. I was told he looked like a teenager, as surprised to see the foreigners as much as they him. He quickly left for another rooftop.

Fear of the shooting, and of encountering troops in the narrow winding alleys where often one sees no more than a few yards ahead, kept most residents in their homes yesterday. I could see a pall of dark smoke rising from an area where the city’s main mosque is located. That area is home to many Hui Muslims, who are as much a target of Tibetan wrath as are the ethnic Han Chinese.

I had seen so many columns of smoke rising from the area around the hotel since Friday that I thought little of it. In the middle of the night I was awakened by a hammering on my door and was summoned to the roof. Residents were gathered on rooftops all round the hotel. Rumour had spread that Huis were preparing a revenge attack. Some had gathered stones to throw down on the Hui if they approached.

They never did. The part of the city near the Jokhang Temple, the holiest of Tibetan holy sites, was completely silent yesterday, apart from the odd gunshot. There were no pilgrims heading to the Jokhang, no shoppers and certainly no tourists: many hotels have been refusing to let them out except to go to the airport.

From our hotel rooftop, crouching low as is now the norm, I saw a patrol of troops disappearing around a corner. They appeared to have two Tibetan women with them. Under arrest? Escorting them home? It was impossible to tell. For the first time since the rioting began on Friday there was no sign during the day of any attempt to gather on the streets.

One Tibetan said that he saw troops with rifles clustered on a nearby rooftop.

Polite officials from the Tibetan government’s Foreign Affairs Office visited the hotel yesterday. One said he wanted to relay the concerns of his bosses about my welfare. He was concerned too about the supply of food and offered to help if I wanted to leave before my permit expired. It might be difficult, he said, to arrange a ticket because so many were trying to leave Tibet. I thanked him for the offer. The two officials headed back to their car, which they said they had had to leave parked a distance away because of the security cordon.

The worry now is about tonight’s deadline. Will this be followed by knocks on doors and sweeping, indiscriminate arrests? Many Tibetans keep pictures of the Dalai Lama in their homes. I imagine now that they are busy secreting them.

James Miles is the China correspondent for The Economist

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