Russia said that a “regime of calm” truce in the Syrian city of Aleppo and parts of Latakia province had been extended “for 72 hours beginning at 1 a.m. on Saturday” after Moscow was slammed for blocking a U.N. Security Council statement condemning the regime’s offensive in the northern city.

A fragile local truce had been in place for Aleppo city since early on Wednesday. In northern Latakia province, it first took effect on April 29, after a wider truce deal in western Syria brokered by Washington and Moscow broke down.

The Security Council statement was circulated to the 15 members on Wednesday during an emergency meeting on Aleppo but was dismissed by Russian Ambassador Vitaly Churkin as a “propaganda coup.”

British Ambassador Matthew Rycroft said Russia’s refusal to back the statement “speaks volumes about their support for and protection of the Assad regime.”

After at least 28 civilians were killed in air strikes that hit a camp of displaced Syrians in Idlib province near the Turkish border on Thursday, the British ambassador called for more pressure to be exerted to rein in the Damascus regime.

“It is really high time for every member of the Security Council to use every last drop of influence on the Assad regime to get them to respect the cessation of hostilities and every other obligation under international humanitarian law,” said Rycroft.

At the emergency meeting, U.N. Humanitarian Coordinator Steven O’Brien said those responsible for repeated unconscionable acts of inhumanity in Syria must know that they will one day be held accountable.

O’Brien said he was “horrified” by the further death and destruction in Aleppo. He said the targeting of medical facilities not only claimed innocent lives but left thousands of civilians unable to obtain the most basic levels of care.

U.N. Under-Secretary-General for Political Affairs Jeffery Feltman said the pattern of “systematic destruction is evident in Aleppo.”

He said there were “horrifying images of attacks on hospitals” in both regime and opposition-held neighborhoods of the city. “Let me be absolutely clear once again: intentional and direct attacks on hospitals are war crimes,” he declared.

Meanwhile, in central Syria, regime forces launched an assault against a prison in the central city of Hama aimed at ending a mutiny, the Syrian Observatory for Human Rights said.

The mutiny began on Monday after an attempt to transfer inmates to the military-run Saydnaya prison near Damascus.

Authorities had earlier cut electricity to the prison and prevented food from getting in, the Britain-based Observatory said.

The opposition’s High Negotiations Committee called on international aid groups to help those in the prison.

“They are firing live bullets and tear gas inside … we are unarmed,” said one of the prisoners, speaking in an audio message sent to The Associated Press by phone. He also sent two video clips showing men having breathing problems, apparently after inhaling tear gas.

The Observatory said live bullets were being used in the operation, adding that some of the prisoners have fainted because of tear gas.