ALGIERS, Algeria (AP) _ Talaat Yacoub, the leader of a hard-line faction of the Palestine Liberation Organization, has died of a heart attack, Algerian television reported Friday.

Medical sources said Yacoub, who was in his 40s, had no history of heart trouble. The sources spoke on condition of anonymity.

Another source said the announcement of his Thursday death was delayed to avoid ''saddening'' the declaration of an independent Palestinian state in Israeli-occupied territories. The PLO's parliament-in-exile, the Palestine National Council, made the declaration Tuesday during a meeting in Algiers.

Yacoub was one of the PLO's lesser known guerrilla leaders. He led a pro- Syrian, pro-Libyan faction known as the Palestine Liberation Front.

Algerian television provided no details on where Yacoub died. No information was immediately available on funeral plans.