A man in Wisconsin is accused of repeatedly hitting an elderly bus driver because he claimed he was having a bad day and believed the driver had his phone, according to authorities.

Anthony Miller, 23, faces charges of battery against a public transit operator and intentionally causing bodily harm to an elderly person, as stated in Milwaukee County court records.

The incident occurred on July 18.

It is reported that Miller got off a Milwaukee County Transit System (MCTS) bus around 10:30 a.m. on the specified date, based on a criminal complaint viewed by local Fox station WITI.

The 72-year-old bus driver stated that the suspect “forced his way back onto the bus by pushing in the door and began shouting at the driver, demanding to know where his phone was,” according to the charges.

The passenger then “forced himself beyond the security plexiglass meant to protect the driver and proceeded to punch the driver in the face approximately 20 times with a closed fist,” as per the complaint.

The driver is said to have suffered a 4-inch laceration on his forehead which later required four stitches, as well as pain and swelling all over his face and head. After the attack, the suspect left.

Milwaukee police reportedly arrived on the scene at Teutonia and Florist avenues shortly after, being told a bus driver was assaulted. Video surveillance helped detectives identify Miller as their suspect, authorities allege.

First, investigators had the account of the bus driver. Then came the suspect’s story. Miller was interviewed on Wednesday, WITI reported, where he admitted he was involved in an incident on a county bus. The attack apparently could be traced back to one thing: “he was having a bad day,” authorities wrote.

Miller reportedly described “having to come up with rent and having his car being stolen,” and once he exited the bus, he realized he dropped or forgot his phone and believed the bus driver had it.

The suspect allegedly told police “the bus driver assaulted him so he assaulted the bus driver back,” failing to remember how many times he hit the driver in total.

Miller was arrested on Wednesday and is being held on $5,000 bail. He has a preliminary hearing scheduled for Aug. 25.