The Metropolitan Transportation Authority says it is working with police to investigate three separate attacks on train operators over the weekend.

All three attacks took place over a two-hour span Saturday night.

In the first incident, a train operator was punched in the face at the Essex Street stop on the J train.

About an hour later, another rider hit a C train operator with a beer can at the Euclid Avenue stop.

The third attack came later that night when a rider spat in the face of a G train operator at Court Square.

No arrests have been made.

In a statement, an MTA spokesman says, "An assault on our employees is an attack on all of us. These incidents are extremely disturbing and we remain committed to the safety and security of our employees."