ANKARA, Turkey (AP) _ Leftist prisoners fasted for a 69th day, refusing to halt their nationwide hunger strike for better prison conditions despite government threats to force an end.

Three more inmates died today, bringing the death toll to 11. About 100 protesters reportedly were critically ill.

The government has threatened to storm an Istanbul prison unless 2,000 inmates end their fast. It claims inmates at the Bayrampasa prison are leading the strike.

``We'll have to intervene if they don't give up voluntarily,'' Justice Minister Sevket Kazan said Friday.

Hicabi Kucuk died today in the western city of Bursa, the independent Human Right Association announced. Yemliha Kaya died at Bayrampasa and Osman Akgun died at Umraniye, another Istanbul prison. Kucuk and Kaya had been on trial for membership in an outlawed left-wing group. Akgun was serving a life sentence for participating in terrorist acts by an illegal leftist group.

The inmates and human rights groups allege widespread torture and other abuses behind bars, especially against suspected terrorists and rebels.

The inmates are demanding better access to legal defense and medical treatment and an end to transfers and beatings in jails. They also want previous transfers from Istanbul's two prisons to be reversed.

Amnesty International, the London-based international human rights group, said prisoners were right to resist transfers.

``Transfers are always brutal and have been fatal several times in the recent past,'' said Jonathan Sugden of Amnesty International.

Kazan ruled out reversing the transfers, saying the inmates' objective was to have their recruits back for ``terrorist training.''

He said his ministry would not negotiate with prisoners, but he would allow two prominent Turkish writers to visit Bayrampasa prison and try to persuade inmates to end their strike.

One of the writers, Yasar Kemal, declined the offer.

``The government is telling us they will not accept any demands,'' Kemal said. ``So they are not asking us to negotiate but just to `convince' prisoners to give up,'' Kemal said. ``I don't see any hope of ending this peacefully.''

The strikers and fellow inmates have kept medical teams from entering prisons. Kazan blamed the deaths on ``ring-leaders inside prison who have hand-picked the victims and ordered them to die.'' He said prosecutors would charge them with instigating murder.

Kazan said authorities couldn't force-feed or remove inmates for medical care because they were not in control of some 19 wards housing 820 prisoners at the Bayrampasa prison. He could not say why troops were unable to move in to smaller prisons where deaths have also occurred.

The strikers are either on trial or have been convicted of membership in outlawed leftist groups or the Kurdish uprising. Some have been involved in murders or bombings.

Some 4,000 Kurdish prisoners joined the strike Friday in a move of solidarity.

Kurdish rebels set fire to an inter-city bus today in eastern Turkey after asking the passengers to get off, the Anatolia news agency reported. The rebels told the passengers their action was in support of the hunger strikes.

Various rallies erupted Friday in Istanbul, Ankara and Izmir _ Turkey's largest cities _ where protesters demanded Kazan's resignation.

``The prisoners' demands are all humane and could be met easily,'' Erol Anar, an official from the Ankara-based Human Rights Association, told The Associated Press.

``But the new government is trying to prove itself and present a state with an iron fist which can stand all assaults,'' Anar said.