Two trains have collided in the Czech Republic, killing at least three people and injuring dozens more. The Munich-to-Prague express collided with a regional train between the Czech towns of Plzen and Domazlice, which was coming from the opposite direction shortly before 8am local time. Police said at least three people died in the crash. The victims included the drivers of both engines and a female passenger, authorities said. Four people who were seriously injured were taken away by helicopter, and seven others required surgery. The regional rescue service said a total of 52 people needed treatment. An international high-speed train connects the western Czech city of Plzen with Munich in Germany. Czech Transport Minister Karel Havlicek said it was likely that human error caused the crash. "The Ex 351 did not respect a signal ... and crashed into the regional train," he said. "The situation is serious." Czech Prime Minister Andrej Babis tweeted his "sincere condolences to the families of the dead. It is important to save other lives. Then everything must be investigated." "Unfortunately, this summer is full of tragedies," he said. Footage on Czech Television showed the smashed driver's cabin of the high-speed train, as well as the front part of the local train. Both remained upright on or near the tracks. CTK news agency said emergency services sent four helicopters to respond to the crash. Commander Jaroslav Hrdlicka of the regional fire department said rescue workers were still looking for a missing person in the wreckage Two train crashes in the Czech Republic in July last year left three people dead and dozens injured. <br/>