Around 1,400 visitors to the Eiffel Tower were rushed out of the world-famous monument after an anonymous phone call threatening an attack on Saturday night, police said. French police stand guard near the Eiffel Tower in Paris on March 30, 2013. AFPThe tower was reopened after around two and a half hours after police searches failed to find any suspicious objects. The call came from the Paris suburbs and threatened an attack at 9:30 pm (2030 GMT), police said. Police anti-terrorism officers were investigating. Bomb alerts targeting monuments and public places happen frequently in Paris, but all alerts are “treated very seriously,” police said.