Amid conflicting reports of the incident, AP quoted Palestinian hospital sources as saying the death brought to four the number of people killed in the shooting on the Gaza-Israel border on Wednesday night.
The Palestinian hospital officials said one policeman and three fighters were killed and four people wounded by Israeli tank machine-gun fire late on Wednesday, among them a seven-year-old child.
However, AFP reported Palestinian medical sources as saying that the man who died on Thursday was the third of three Palestinian policemen to have died of his wounds after being hit.
AFP said that two Palestinian policemen were killed immediately and four others wounded in the incident near the Karni crossing between the Gaza Strip and Israel.
The seven officers from the Palestinian national security service were on patrol near the crossing when they came under fire from machine guns mounted on Israeli tanks just over the border, AFP said quoting security sources.
An Israeli military spokeswoman confirmed that soldiers had spotted "three suspect silhouettes approaching the security fence that guards Israeli territory and opened fire in their direction".
She was unable to say whether the targets were armed.