An animal keeper at a zoo in Madrid suffered serious injuries after being viciously mauled by a gorilla.

The 29-year-old gorilla, named Malabo, attacked the zookeeper when he entered a protected area of the zoo for routine feeding and cleaning Sunday morning, zoo officials said in a statement.

"The events took place this morning, around 10 a.m. when a keeper with 19 years of experience at the zoo accessed the indoor facilities for the usual breakfast routine, cleaning and preparing the facilities," the statement read. "Upon entering a bounded area with a triple door, the caretaker met Malabo, a 29-year-old male gorilla, who had accessed it."

The area where the incident happened was not open to visitors. How the gorilla managed to enter the area was being internally investigated, the officials said in the statement, adding that a criminal investigation was also going on.

The 46-year-old zookeeper, who was not identified, was treated by paramedics at the scene and was rushed to the Madrid Clinical Hospital in a serious condition. According to local media reports, the person was left with two broken arms, suffered a head injury and chest trauma following the attack.

Madrid emergency agency posted images on Twitter that showed paramedics carrying the injured zookeeper on a stretcher to an ambulance.

Other employees at the facility removed Malabo, which reportedly weighed over 400 pounds, from the area and a team of veterinarians anesthetized it. The statement said it was "calm" after being tranquilized.

"It should be noted that this interior area is for driving, with no exit to the public area and in this sense, the emergency protocol was quickly activated, notifying the Samur emergency team and the municipal police," the statement read.

The Madrid police were investigating the incident.

Harambe Gorilla
Harambe, a 17-year-old gorilla at the Cincinnati Zoo, is pictured in this undated handout photo provided by the Cincinnati Zoo. Reuters