Turkish security forces used earth-moving equipment to demolish walls in a jail yesterday, the second day of a crackdown on hunger-striking inmates in scores of jails that the Prime Minister, Mr Bulent Ecevit, described as "terrorist dens".
The nationwide operation, which began on Tuesday, has already claimed at least 19 lives - 17 inmates and two soldiers.
The NTV news channel showed several walls of a prison in Canakkale city partially demolished, while others had huge holes, with earth-moving machines standing by.
Paramilitary soldiers had reportedly entered the building in which inmates had barricaded themselves, but no further details were available.
Hundreds of prisoners have been on hunger-strike for more than two months protesting against reforms which they claim could expose them to increased repression.
Turkey wants to put an end to dormitories housing up to 60 inmates which are insecure and replace them with smaller units with three in each cell.
Elsewhere, earth-moving machines, fire-fighting vehicles and buses carrying riot police as well as ambulances were seen entering a prison in Umraniye district on Istanbul's Asian side, Anatolia news agency reported.
The Umraniye and Canakkale jails were the only two that security forces failed to break into on Tuesday when hundreds of riot police and soldiers stormed 20 prisons across Turkey. The assault was to end the hunger-strike after lengthy mediation efforts failed.
"I appeal once again to inmates to stop this meaningless resistance. It will lead nowhere," the Justice Minister, Mr Hikmet Sami Turk, said yesterday. "We think the operations will end today. The security forces are acting with utmost caution" in order to prevent further deaths, he added.
The European Commission expressed concern yesterday at the crackdown by Ankara, whose bid for EU membership depends on improving its human rights record and democratic institutions.
"We are worried," said an EU spokesman, Mr Jean-Christophe Filori, in Brussels. "We call upon all parties to stop the violence in order to reach a peaceful outcome."
Amnesty International called for an immediate and independent inquiry into the raids, and said anyone held responsible for deaths should be suspended from duty pending its outcome.
The number of inmate victims rose to 17 yesterday after a prisoner died in an Ankara hospital from severe burns caused by self-immolation, Anatolia said.
Most of the inmates died after setting themselves ablaze in line with orders by outlawed groups they belonged to, Mr Turk said, adding that some 80 prisoners were injured.
Two soldiers were killed in separate clashes with inmates in Umraniye and Canakkale prisons, while four were wounded.
Ankara says the strikes and inmates' resistance were orchestrated by outlawed armed groups, mainly from the extreme left, and many strikers were forced to starve.
"Terrorist dens are being eradicated with these operations," Mr Ecevit said. "Those terrorists must have finally understood that they cannot overwhelm the state."