A San Francisco man was arrested on suspicion of stabbing two men in the head with a screwdriver on a Fremont-bound BART train, then stealing another man’s bicycle at knifepoint, police said Monday.

Ronald Nalls, 48, was booked on two counts of attempted murder, two counts of assault with a deadly weapon and three counts of robbery, BART Police said.

Authorities received reports about 7:15 p.m. Saturday of a fight and possible stabbing aboard a train nearing the Fremont Station. An investigation revealed the suspect stabbed two men on the train with a screwdriver, then robbed them of undisclosed belongings, said BART Police Sgt. John Power.

Police said Nalls fled the train after two people tried to restrain him. When he reached the street level he reportedly robbed a man of his bicycle at knifepoint, Power said.

Nalls began pedaling south but was detained by Fremont police officers responding to the call. Officials did not immediately disclose the condition of the injured victims. Both were hospitalized after the incident, Power said.

Police later recovered all of the victims’ belongings.

The train that the stabbings occurred on was held for about an hour to allow police to process the crime scene.

Nalls was being held without bail at Santa Rita jail in Dublin.

The assault comes days after a stabbing victim was found at a Civic Center BART Station platform in San Francisco. The victim, whose name has not been released, was attacked on the street Wednesday before running into the station with three stab wounds.

On Friday, 22-year-old Roger Ortiz was arrested on suspicion of attempted murder in connection with the Civic Center BART Station stabbing, officials said. He was booked into San Francisco County jail without bail.

Jenna Lyons is a San Francisco Chronicle staff writer. Email: jlyons@sfchronicle.com Twitter: @JennaJourno