PORT NECHES, Texas (AP) — A chemical company says three people were injured in an explosion at its plant in East Texas. The powerful blast blew out the windows of homes and sent a chemical plume blowing over neighborhoods miles away.

The explosion happened at about 1 a.m. Wednesday at the TPC Group Port Neches plant, which produces chemical and petroleum-based products. Fires were still burning hours later, lighting up the night sky with orange flames and thick smoke near the Louisiana state line.

The Nederland Volunteer Fire Department warned people living south of Interstate 10 near the plant to minimize their exposure to the chemical plume by sheltering in place, closing windows and turning off their heating and air conditioning systems. A mandatory evacuation was ordered for everyone within a half-mile of the TPC plant, and the fire department said that evacuation could expand to a wider area.

A statement by TPC Group said all personnel at the site have been evacuated and accounted for, and three people were being treated for injuries.

KDFM TV in Beaumont reported that County Judge Jeff Branick says it’s a miracle that no one died. Branick said one worker suffered burns and was taken by medical helicopter to a Houston hospital. The others had a broken wrist and a broken leg.