A detention officer was hospitalized late Saturday after police say he was attacked while walking to his car in downtown Los Angeles, according to the Los Angeles Police Department.

The incident was reported just after 10 p.m. near the Metropolitan Detention Center. There, the detention officer was attacked by an unknown number of individuals, LAPD claims.

By the time police officers responded to the scene, the attackers had already fled, police said. A description of those individuals was not available. Law enforcement did not disclose what led up to the incdent.

As a result, the officer was taken to a nearby hospital. The severity of his injuries was not disclosed.

Police said when the attack happened, a protest of about 40 to 50 people was taking place outside the detention center. One person was arrested for interfering with police in a charge that was not related to the attack.

The investigation is ongoing.