A woman estimated in her 30s allegedly threatened the two women, both in their 20s, and hit one of them across the face after they got off the bus in the city centre.

Police say the incident came about after one of the victims accidentally bumped her bag into the attacker while getting on the bus in Port Melbourne around 12.30pm on December 12.

The victim turned to apologise, police say, but instead copped a racist verbal attack.

The victims left the bus after the abuse continued but were followed by the woman.

After slapping one, the attacker knocked a phone from the other victim’s hand as she was attempting to call police.

The attacker then fled in a taxi, after warning the women not to contact police.

Police have appealed for witnesses to come forward.

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