New York police are now treating the death of America’s first female Muslim judge as “suspicious,” six days after her body was found in the Hudson River.

Sheila Abdus-Salaam, 65, was the first African-American woman to serve on New York’s Court of Appeals and the first Muslim woman to serve as a US judge.

Her body was found floating in three feet of water near Manhattan’s west side on Wednesday afternoon last week. She had last spoken to her husband at 7pm on Monday and spoken to her assistant on Tuesday.

Police said at the time that Ms Abdus-Salaam’s body was found fully clothed and showed no obvious signs of trauma. Her death was initially treated as a suicide, with one law enforcement official stating that both the judge’s mother and brother had died in recent years around Easter. Her brother had taken his own life.

Investigators are now treating her death as suspicious, adding that there is no “clear indication” of criminality or suicide.

“We’re looking at it as a suspicious death at this point. We haven’t found any clear indications of criminality, but at this point we can’t say for sure. We’re hoping if anyone could shed any light into the hours before her disappearance, it would help us establish what happened,” NYPD spokesman Stephen Davis told ABC7NY.

The New York Police Department tweeted a public aqppeal notice asking anyone with information to contact the 26th Precinct Detective Squad.

Investigators are studying surveillance video footage from shops and residential buildings to try and piece together Ms Abdus-Salaam’s last movements, the New York Post reported.

The newspaper cited sources as saying there had been no signs of forced entry or a struggle at the judge’s Harlem apartment. They also said the autopsy found water in her lungs and slight bruising around her neck, but her eyes did not show the type of bleeding associated with strangulation. Official autopsy results have not yet been released.

Ms Abdus-Salaam graduated from Barnard College and received her law degree from Columbia Law School.

She started her career as a staff attorney for East Brooklyn Legal Services and later served as a judge on the Manhattan state Supreme Court for 14 years. She was appointed to New York state’s Court of Appeals in 2013.