A vehicle belonging to the United Nations observer mission in Syria was struck by a bullet over the weekend, U.N. spokesman Martin Nesirky said Monday. There were no injuries and no significant damage, and it was unclear who fired the bullet, Nesirky said. Nesirky said 189 military observers have been deployed to Syria as of Sunday, and the full mandated force of 300 unarmed observers is expected to be on the ground by May 30.