A 23-year-old Mastic man is under arrest following two shocking and apparently random stabbings in Riverhead and on a Suffolk County bus last week, according to authorities.

The suspect, Rene Alexander Elias Chaj, is accused of carrying out both attacks in a span of an hour on the afternoon of May 2. The first incident occurred at the Time to Eat Deli on West Main Street in Riverhead, where police say a victim was stabbed without provocation. Investigators noted there was no prior interaction between the suspect and the victim.

Moments later, Chaj allegedly boarded a Suffolk Transit bus and stabbed another passenger while the vehicle was traveling along County Road 51 near the Suffolk County Center. He was taken into custody shortly afterward by Southampton Town Police.

“That someone could get on a bus right afterwards and continue to go on a rampage—it’s a little frightening,” said Amy Sponza of Greenport.

The seemingly random nature of the violence has left many East End residents shaken.

“Randomly, you’re out on your day and next thing you know you’re getting stabbed by somebody. That’s wild,” said Reggie Johnson of Shelter Island.

While Southampton Town police notified the public of the arrest the same day, Riverhead police waited a full week.

A Riverhead police official explained the delay, saying the suspect was initially arrested in a different jurisdiction.

Chaj has appeared before judges in both Riverhead and Southampton on multiple charges, including assault, criminal possession of a weapon and drug possession. Authorities say he was found to be in possession of cocaine at the time of his arrest.

He is currently being held at the Suffolk County Jail.