Groups of men gathered in the early morning in several places across the capital, alarming Sunni Muslim residents who said they were supporters of Hezbollah or its Shi'ite ally Amal.In May 2008, armed supporters of Hezbollah took over parts of Beirut after government steps to shut down its private telecommunications network and curb its control at the airport. Dozens of people were killed in fighting across the country.Last week Hezbollah ministers and their allies toppled the government of Prime Minister Saad al-Hariri, son of the slain Sunni leader, after he refused to cut Lebanon's ties with the U.N.-backed tribunal investigating his father's killing.The tribunal prosecutor issued a draft indictment on Monday. Its contents were not revealed, but it is expected to accuse members of Hezbollah, which denies any role in the assassination and had accused the tribunal of being an "Israeli tool".Shi'ite Speaker of Parliament Nabih Berri told As-Safir newspaper that the opposition had said that its policy would change once the indictment was issued, and that policy "has entered the stage of implementation as of yesterday afternoon".The appearance of dozens of men across the capital raised fears of a repeat of the conflict in 2008."I got a call from my mother to come home immediately because the situation is bad, and there are people on the streets," said university student Mira Noureddine. "We are worried the situation could get worse".Lebanon's Education Minister Hassan Mneimneh said schools would remain open. "Despite the gatherings of youths we have seen briefly on the streets this morning, schools are continuing their normal operation".But Heba Nashabe, principal at a school in the central Beirut district of Barbir, said she had only four students out of 1,800 on Tuesday. "The parents came and took the students from eight o'clock in the morning because they were frightened.""There are two other schools which are closed."Security forces closed a road in central Beirut leading to the Ottoman-era government offices, and soldiers were deployed along the airport road, witnesses said, ahead of a visit by Turkey's foreign minister and the prime minister of Qatar.The two men were due to hold talks in Beirut on Lebanon's political crisis, after a summit meeting in Damascus on Monday between the leaders of Syria, Qatar and Turkey.