BEIRUT (AP) — Runners taking part in Lebanon's annual marathon are urging Prime Minister Saad Hariri to return home after he resigned under mysterious circumstances during a visit to Saudi Arabia.

Spectators along the 26.2 mile (42.2 kilometer) course held signs reading "Running for you" and "Waiting for you," addressed to the prime minister, who participated in past races. Lebanese President Michel Aoun had encouraged runners to call on Hariri to return.

Hariri, a close Saudi ally, unexpectedly announced his resignation a week ago in a pre-recorded message broadcast on Saudi TV. Many Lebanese suspect he was placed under house arrest as part of a Saudi plan to wreck a coalition government he had formed with Hezbollah.

Saudi Arabia has stepped up its rhetoric against Hezbollah and its patron, Iran, in recent days.