Hungary's transport minister and railways chief both resigned on Monday after a train crash killed four people and injured 26, state news agency MTI said.

Two trains collided on a bend, 30 km (19 miles) southeast of Budapest, after one of them had slowed because of a faulty signal, a spokesman for state railway MAV said.

Transport Minister Pal Szabo and MAV Chief Executive Istvan Heinczinger resigned following the crash, MTI said.

Transport experts say heavily indebted MAV needs investment to upgrade its aging infrastructure and rolling stock. MAV is Hungary's largest employer and racks up large losses every year, forcing the government to regularly bail it out.