A suburban passenger train collided with a freight train in Athens Thursday, injuring at least 45 people, authorities said.

The crash occurred at 7:25 a.m. in the western Athens area of Sepolia. None of the injuries appeared to be serious, police and officials at three state hospitals where the injured were taken said.

State-run NET television said 53 people had been injured, but authorities could not immediately confirm that figure.

The cause of the accident was not immediately clear, but the Greek Railworkers' Association said the two trains were using the same track and should not have been.

"This is the kind of practice that will lead to an accident sooner or later. ... These two trains should not have been using the same track," the association's leader Andreas Vassilopoulos said.

The passenger train was headed to the port of Piraeus, near Athens, when the collision occurred. Neither of the trains derailed.

Greece's state-run Hellenic Railways, or OSE, has suffered several derailments and other accidents this year.

In February, a freight train transporting armored personnel carriers for the Greek army derailed in northern Greece.

In March, three people were killed when a passenger train hit a car at a rail crossing 20 miles north of Athens. The following month, a passenger train crashed into a truck at a crossing in northern Greece and derailed, killing four people and injuring at least 40.