MARAWI, Lanao del Sur - (UPDATED) As the Muslims in this besieged city offered prayers at the end of Ramadan, suspected gunshots were heard early Sunday, just minutes after state troops implemented an 8-hour ceasefire to give way to the celebration of Eid al-Fitr.

The gunshots were heard around 6:50 a.m. in the background of a radio DZMM live report about congressional prayers for the Eid al-Fitr celebration held at the provincial capitol building.

A stray bullet was then reportedly found at the capitol building.

No one was reported injured in the incident. Authorities, however, have yet to confirm the source of the alleged gunfire.

DZMM's Edwin Sevidal said an explosion somewhere from the conflict zone was heard a few minutes before 2 p.m., while the sound of continuous gunfire was also heard at exactly 2 p.m.

The military had suspended offensives against Islamic State-inspired extremists holed up in Marawi City from 6 a.m. to 2 p.m. Sunday.

The "humanitarian pause" was the government's "way of uniting with all our Muslim brothers in the area as they commemorate the Eid," military spokesman Brig. Gen. Restituto Padilla told ANC.

Padilla said the unilateral truce will be revoked if the enemy starts firing and jeopardizes the safety of troops and civilians.

The officials also guaranteed that state troops continued to keep a close watch at all entry and exit points in Marawi amid the ceasefire.

"We are confident that the measure we have out in place will prevent any influx of help that may come from other areas and the escape of those who are still inside," said Padilla.

'LONELIEST FEAST'

Some 300 people have been killed while tens of thousands were displaced by weeks of fighting between government troops and Maute extremists in Marawi.

Local officials at the capitol building said this year Eid celebration is the saddest in recent memory.

Terrorists who stormed the city, they said, robbed them of the chance to celebrate the Muslim feast with their loved ones.

The local leaders said they will pray for the over 260,000 Marawi residents who were forced to flee to evacuation centers. -- With reports from Ron Gagalac and Edwin Sevidal, ABS-CBN News

• MORE STORIES: Marawi siege, martial law in Mindanao