BRISTOL — Avon and Somerset police declared a major incident after an explosion at a residential address in the Frenchay area of Bristol killed two adults on Sunday morning. The force said it was treating the cause of the blast as suspicious but had ruled out terrorism.

The explosion occurred at about 6.30am at a property on Sterncourt Road. A security cordon was placed around the address, local roads were closed, and residents of nearby houses were evacuated to a temporary rest centre at a nearby Harvester pub.

Emergency service vehicles including police cars, ambulances and a bomb disposal van were present at the scene. Neighbours reported seeing armed police officers outside the house. Officers were also carrying out inquiries at a property in Speedwell linked to the incident.

"An explosion was reported at a residential address in Sterncourt Road at about 6.30am today. The cause of the incident is being treated as suspicious, and a major incident has been declared. Two adults have died at the address and their families have been updated." a police spokesperson said.

The force said there was not believed to have been any damage to neighbouring properties. "Emergency services are following well-rehearsed plans in response to this incident." the spokesperson said.

"Our inquiries are at an early stage, but at this point we are not looking for anyone else in connection with this incident." the spokesperson said. "Given the recent change to the UK threat level, we would like to reassure the public from the outset we are not treating this as a suspected terrorist incident."

The spokesperson asked the public not to speculate about the circumstances and to avoid the area while emergency services responded. "We ask people not to speculate around the circumstances and continue to encourage the public to avoid the area while emergency services respond to this incident." the spokesperson said.