Police are conducting a “terrorist investigation” following the stabbings of three people at a railway station in Manchester, northern England, during New Year’s Eve celebrations, authorities said.

A male police officer was stabbed in the shoulder, and another man and a woman were taken to a hospital with serious knife injuries after the “horrific” attack just before 9 p.m. (4 p.m. ET) Monday at the Manchester Victoria railway station, Greater Manchester Police (GMP) said in a statement.

Police have arrested a man involved in the attack and were searching his home in Manchester on Tuesday in an effort to piece together his identity.

“Last night we experienced a horrific attack on people out to simply enjoy the New Year’s Eve celebrations in Manchester,” Manchester Chief Constable Ian Hopkins said in a statement.

He added that counter terrorism officers were leading the investigation into the attack, which happened close to the scene of the “dreadful” Manchester Arena bombing that killed 22 people in May 2017.

Hopkins said police officers “acted with incredible bravery in tackling the armed attacker at the busy Metrolink station and ensured he was immediately detained.”

The attacker remains in custody in Manchester.

BBC producer Sam Clack was on the platform when the attack took place. Clack told the British broadcaster he heard a “blood-curdling scream” and observed what “looked like a fight going on … sort of scuffle.”

He heard the man distinctly shout “Allah,” he said, but he didn’t hear the rest of the sentence.

“The police were on the platform very quickly,” he said. Police used pepper spray and a Taser to get the man to the ground, Clack said. “He was very much resisting arrest.”

Shortly after the incident, Clack said on Twitter that he had, “Just been very close to the most terrifying thing. Man stabbed in Manchester Victoria station on tram platform. Feet from me, I was close to jumping on the tracks as attacker had long kitchen knife. Totally shaken. This is seriously messed up.”

The two other victims, both in their 50s, suffered injuries to their abdomens and the woman suffered additional injures to her face, police said, though their wounds are not considered to be life-threatening.

New Year’s Eve fireworks at Albert Square went on as planned despite the incident, according to the Manchester City Council.