The Democratic mayor of the city where a Ukrainian refugee was allegedly stabbed to death by a known criminal has called for “compassion” for the suspect.

Vi Lyles, the mayor of Charlotte, North Carolina, said she did not want to “villianise” Decarlos Brown Jr, who is accused of murdering Iryna Zarutska, 23, in an unprovoked attack.

Ms Lyles said that Charlotte “must do better” for people like Mr Brown, who is homeless, as they “need help and have no place to go”.

The comments led to calls on social media for Ms Lyles to resign, with some branding her a “total lunatic” and calling for Donald Trump to send in the National Guard.

The US president said Ms Zarutska was killed by a “madman” and called the incident “evil”.

First-degree murder charges

Mr Brown, 35, who has been arrested 14 times and spent six years in prison for robbery and larceny, is accused of stabbing Ms Zarutska to death on a light rail train in Charlotte on Aug 22.

He faces first-degree murder charges, and a judge has ordered him to be evaluated for the next 60 days at a local hospital.

Disturbing surveillance footage released by the Charlotte area transit system shows the young woman boarding the train and taking a seat in front of Mr Brown, who appears agitated and restless in his seat.

Five minutes into the journey, Mr Brown appears to pull out a fold-out pocket knife, before standing up, and swinging his arm high before allegedly stabbing her three times in the neck.