Beirut - Syrian regime air strikes halted on Friday in the country’s northwest after a truce went into effect there but ground fire killed at least one person in a regime-held village near Bashar Al Assad’s hometown, state media and opposition activists said.

The conditional cease-fire went into effect at midnight Thursday, according to Syrian regime media which quoted an unnamed military official.

The reports said the rebels will have to retreat 20km from demilitarised areas around the stronghold that were agreed to in a cease-fire deal reached last September. That deal had crumbled as Al Assad’s forces in April launched an assault on Idlib, the last rebel stronghold in the country.

Syrian regime news agency SANA said rebels fired five rockets into a village near Al Assad’s hometown of Qardaha, killing one civilian and wounding three others.

The Britain-based Syrian Observatory for Human Rights said Idlib was witnessing “cautious calm” on Friday as warplanes stopped flying over the province. The Observatory, which monitors Syria’s war through a network of activists on the ground, also said that regime forces fired about 50 shells in the morning hours at rebel-held villages in northern parts of the central province of Hama.

Ahmad Sheikho of the opposition Syrian Civil Defence volunteers, also known as White Helmets, said that since midnight, “there are no warplanes in the air” but that artillery shelling continued.

Speaking about the truce, Syria’s UN Ambassador Bashar Ja’afari appeared to be sceptical, saying that thousands of foreign fighters remain in Idlib, describing them as part of an “international terrorist project.”

He was referring to foreign fighters - Al Qaida-linked militants and other extremist groups in Idlib - and also Turkish forces inside Syria.

Ankara has launched several offensives inside Syria, drawing the ire of Al Assad’s regime, and maintains bases alongside its border - mainly to keep US-allied Syrian Kurdish fighters from expanding their territory. Turkey considers a Syrian Kurdish militia that has battled militants as terrorists linked with a Kurdish insurgency within Turkey.

Turkey also has 12 observation posts that ring Idlib, following a de-escalation agreement reached last year with Russia.

“The truce is to test Turkish intentions,” Ja’afari said in the Kazakh capital of Nur-Sultan where an international meeting on Syria wrapped up on Friday.

He added that the cease-fire was conditional on the implementation of the cease-fire reached last year between Turkey and Russia to establish a demilitarised zone in Idlib.

The truce went into effect hours after U.N. Secretary-General Antonio Guterres authorized an investigation into attacks on health facilities and schools in the rebel-held enclave, following a petition from Security Council members.

The offensive in Idlib and surrounding areas has displaced more than 400,000 people and killing hundreds. The rebel-held province is home to some 3 million people, many of them internally displaced by fighting in other areas in Syria.