Police have identified the man whose corpse washed up on Manhattan Beach Monday. Peter Martinez, 28, was wrapped in a plastic garbage bag with his hands tied behind his back and his feet in a bucket of cement when a student found his body near Kingsborough Community College at around 10 a.m., according to authorities. The Medical Examiner’s Office performed an autopsy Tuesday, but has not announced the cause of death. It was not clear if Martinez was dead or alive when he was cemented into the bucket and dumped into the water, authorities said.

A crazed cyclist attacked a 59-year-old driver with his bike lock in Greenpoint, striking him in the head and breaking his car’s side-view mirror, police said Wednesday. The two got into a traffic dispute at 7:45 p.m. Monday, when the cyclist got off his bike and whacked the driver’s 2014 Toyota Prius with the lock, cops said. The unidentified biker opened the driver’s door and hit the man in the head with his hands before striking him in the noggin again with the lock, according to police. He rode off on the bike while his bloodied victim waited for an ambulance, police said. The driver was treated for lacerations to the head and the hand at Bellevue Hospital, according to cops.

A driver who fatally struck a pedestrian in Sunset Park was arrested Wednesday, according to police. Yiru Weng, 67, was crossing Sixth Avenue near 52nd Street at around 12:30 p.m. April 20, when Rodsel Pinkhasov, 58, struck him with his Ford E250 van while making a left turn, according to cops. The victim suffered severe head injuries and was taken to Lutheran Hospital, where he died three days later. Pinkhasov has been charged with failure to yield to a pedestrian and failure to exercise due care.

A bicyclist who was hit by a truck in Fordham Heights last week died Wednesday and police have charged the driver, authorities said. Heather Lough, 29, was riding along Southern Boulevard near the Metro- North station at the New York Botanical Garden on April 27 at around 9:30 a.m. when a Ryder truck making a left turn struck her, according to police. The driver, Robert Owens, 45, remained at the scene and Lough was rushed to Jacobi Hospital, where she died.Police have charged Owens with reckless driving and failure to yield.

Two thieves stole an elderly woman’s wallet at a Heartland Village supermarket and bought about $3,000 in gift cards with her credit card, police said Wednesday. The 71-year-old woman was grocery shopping at a Stop & Shop on Richmond Avenue at 1 p.m. April 10, when a man and a woman approached her, according to cops. While they distracted her, the man made off with the victim’s wallet, which contained a Discover card, police said. The crooks then bought the gift cards at a Target in the Staten Island Mall, according to police.

A man slapped a sleeping straphanger in the face on a Jamaica subway train and then menaced him with a knife, authorities said Wednesday. The 46-year-old victim was napping on a bench of an E train near the Jamaica-Van Wyck subway station at around 7:40 a.m. Monday, when the suspect woke him up with a smack to the left cheek, police said. The man then pulled out a knife and threatened the groggy passenger before walking off the train, cops said. The suspect is around 30 years old, cops said.

A thief broke into a Chelsea advertising firm and stole several laptops, authorities said Wednesday.The suspect entered the offices of Gravity Advertising on West 26th Street a little after 6 p.m. April 22 and removed about eight computers. He is approximately 25 years old, stands around 5-foot-10 and weighs 185 pounds. He was wearing a baseball cap and multicolored sneakers.