French President Francois Hollande expressed his solidarity with victims' families Tuesday after a police officer and three other people were killed in a shootout at a Gypsy camp in northern France.

French police were called to a camp in the Somme department earlier in the day, where they were shot at and exchanged fire. Two policemen were hit by bullets — and one died, the president's statement said.

A Paris prosecutor said three members of the camp were also killed, including a baby, a woman and a "grandfather."

A police spokesman said the attacker was injured in the melee and arrested.

The circumstances surrounding the shootout were unclear.