A Melbourne woman was slapped across the face and forced to sit in her front room as a dozen "thugs" ransacked her house in a terrifying home invasion.

Police believe the same young men could be linked to two other street assaults on teenage boys and another home invasion in a violent crime spree in the city's west on Thursday night.

"This is incredibly concerning, the behaviours are abhorrent, it's just thuggish behaviour," Commander Russell Barrett told reporters on Friday.

The 59-year-old woman was struck across the face as the men, described as being of African appearance, smashed the glass door at her Hillside home at 11.30pm on Thursday.

She was forced to sit in her front room as about a dozen men went through her house, stealing electrical items and car keys before they left.

"They slapped her across the face, she received cuts and bruising and property was stolen," Commander Barrett said.

Earlier in the night, a 17-year-old boy walking in Taylors Hills was hit on the legs with a baseball bat and assaulted.

Police believe the same group also punched and kicked a 16-year-old boy in Cairnlea, before stealing his mobile phone and demanding the pass code.

Just after 12.30am the occupants of a house in Delahey heard a large crack as a window beside their door was smashed.

Three males forced entry into the house but fled with a stolen mobile phone after the occupants armed themselves.

"All of the offenders are described by the victims as African youth, so our investigation is focusing on that," Commander Barrett said.

"We're not saying it's organised, but we're certainly saying they're behaving in street gang behaviours."

Police spotted a stolen car at 1.30am and gave chase, but the car was later found crashed into a fence and all the occupants had fled on foot.

No arrests have been made.

"Our intent is to arrest these young people and to lock them up," Commander Barrett said.