MYSTERY surrounds the suspicious death of a woman found unresponsive in a park this morning.

While police are yet to identify the body — found by a witness who reported the grim discovery to emergency services about 2.40am — they said they were not ruling out links to a nearby sexual assault.

The woman was found on a popular field in inner Melbourne by a man who is so far only a witness and is helping police with their inquiries.

Police said they could not comment on what the man was doing in the area at that time, or what the woman might have been doing either.

Her body was found between Royal Parade and Princes Park Drive at Carlton North, a popular area for joggers.

Paramedics worked on the woman at the scene, but she was not able to be revived.

The soccer field is close to the University of Melbourne and its adjoining colleges, surrounded by a busy park and running track.

The field is also near Ikon Park, the home of the Carlton football club.

Police have urged anyone in the area early this morning who might have seen anything suspicious to come forward “as a priority”.

Homicide Squad Acting Inspector Andrew Stamper said they were also keeping an open mind about connections to a recent sexual assault case.

In the separate incident detectives have released a computer generated image of a man who they want to speak to after a woman was sexually assaulted in Parkville in March.

A woman, aged in her 20s, was walking along Gatehouse St near the intersection of Bayles Crescent on March 28 when she was grabbed by a man about 2.35am.

Insp Stamper said they were liaising with the Sexual Crimes Squad on that matter.

“At this stage we have an open mind but obviously we will be considering that matter in relation to this one,” he said.

“We don’t know if they’re linked at this stage.”

He said their investigation would try to get a complete picture of what had happened in recent times in the area.

Police also said they had concerns for people’s safety and asked the community to be vigilant.

They will be ramping up their presence at all times of the day and night on foot, bicycle and in car.

Superintendent David Clayton told people to take responsibility for their safety.

“This is an area of high community activity … so just make sure you have situational awareness, that you’re aware of your surroundings,” he said.

“If you’ve got a mobile phone carry it and if you’ve got any concerns, call police.”

Inspector Stamper said they could not provide any details on the woman’s age, CCTV or any of the circumstances including if there was a weapon used.

“The circumstances are suspicious,” he said.

“There’s a lot of resources being thrown into the investigation.”

The park has been cordoned off with police tape while the investigation continues.

A pair of black shoes were found only metres from the body but it is not yet known if the shoes belonged to the victim or an attacker and police would not comment.

SES volunteers are helping police search around the field for any evidence.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000