An explosion struck a railway track near the capital Colombo on Thursday for the second time in two days but caused no injuries and only minor damage, Reuters quoted the military as saying. The blast hit the rail line near Kelaniya, about 10 km (6 miles) north of Colombo. "Nobody was injured and only about a foot of the track was damaged," military spokesman Brigadier Udaya Nanayakkara said. Earlier, a railway official said all trains on the route were stopped as a precaution. On Wednesday night, a small explosion hit a section of railway line in Mount Lavinia south of the capital but caused no damage or injuries. Authorities said they were still investigating who may be responsible for that explosion. Officials said it was too early to assign blame for Thursday's explosion. Police said a blast that wounded nine in Colombo on Monday was the work of criminals.