Rep. Angie Craig (D-MN) was attacked on Thursday morning in the elevator of her Washington, D.C., apartment building, her office said in a statement quoted in an NBC News report.
"Rep. Craig defended herself from the attacker and suffered bruising, but is otherwise physically okay," chief of staff Nick Coe said in the statement.
Coe said the assailant then fled, and there was no evidence the attack was politically motivated.
A Metropolitan Police Department report detailing the attack obtained by NBC News said that Craig first spotted the suspect in her building's lobby, "acting erratic as if he was under the influence of an unknown substance."
He then entered the elevator with her and began doing pushups before punching her in the chin and grabbing her neck, police said. Craig told police she threw her cup of hot coffee at the assailant, after which he escaped, the report said.
In a statement later Thursday, the US Capitol Police said it is also investigating the attack, but that "there is no indication that the congresswoman was targeted because of her position."
On Thursday night, the Metropolitan Police Department said that a 26-year-old man has been arrested and charged for the assault of Craig.
The suspect was identified in a press release as Kendrick Hamlin, also known as Hamlin Khalil Hamlin.