Two men were attacked on subway trains in the Big Apple on Tuesday morning — one struck with a glass bottle and the other slashed on the hand and arm, cops said. 

A 25-year-old man was riding an A train at 104th Street and Liberty Avenue in Ozone Park at 7 a.m. when a man who appeared to be in his 30s walloped him over the head with the bottle, police said. 

The victim was taken to Jamaica Hospital Medical Center with a cut on his head. 

The attacker, who wore dark clothing, fled. 

The circumstances leading up to the attack were unclear. 

Later in the morning, a 36-year-old man was slashed on the left hand and underarm after a dispute with a 29-year-old woman on a northbound E train at the World Trade Center station around 9:40 a.m., cops said. 

He was taken to Bellevue Hospital, police said. 

The woman was taken into custody, with charges pending, cops said. 

The attacks are the latest in a spate of crime underground.