Police in Florida are seeking the public's help as they continue to investigate the shooting death of Canadian law professor Daniel Markel.

Markel, 41, was shot in the head in his Florida home on the morning of July 18. Police have released few details about his killing but say it is clear he was directly targeted.

On Monday, the Tallahassee Police Department released a statement asking for anyone who may have seen Markel on the day of his death, or the day before. They say he may have been in the area of the Florida State University law school, where he taught; near a local interstate highway, "possibly near commercial/retail establishments"; or near a local synagogue called the Congregation Shomrei Torah Home.

Markel would have been driving a 2008 black Honda Accord with a Florida licence plate, they say.

Last week, Tallahassee police released photos of a "vehicle of interest" in the case and asked for anyone with surveillance in the area to contact police. The car appears to be a silver or light green Toyota Prius, the police report said.

Markel was raised in Toronto and graduated from Harvard Law School in 2001. He had been teaching criminal law at Florida State University since 2005 and became a tenured professor there in 2010.

He had been a well-respected legal academic and his writings had been published in several law reviews and journals.

The father of two had recently gone through a contentious divorce from his ex-wife, a fellow law professor at FSU.