An explosion ripped through a coal mine in Ukraine's western Lviv region Sunday, killing five miners and seriously injuring three others, the Ministry for Emergency Situations said in a statement. Three miners were killed instantly, and two others later died in a hospital. Another three miners were badly injured, the statement said. The methane gas explosion at the Lesnaya mine near the town of Silets occurred when 56 miners were working 550 meters (1,800 feet) underground. Ukrainian prosecutors launched an investigation into the accident, the Associated Press quoted the ministry's statement as saying.