Two passenger trains have collided near the Argentinian capital, Buenos Aires, killing at least 4 people and injuring 70 others. At least 14 of the wounded are seriously hurt.

The crash happened shortly before 9 p.m. local time in San Miguel, 35 kilometers northeast of the capital, when a long-distance train hit a local train from behind.

Firefighters, police and medical workers have been working at the site to bring the situation under control as quickly as possible.

An investigation is underway to find out whether the crash was caused by mechanical failure or human error. It's the second train collision in the past two months in Argentina.