Massachusetts Bay Community College evacuated all three of its campuses and canceled classes and activities for the rest of Tuesday after written bomb threats were found at the school’s Wellesley and Framingham campuses, authorities said. A Wellesley campus security officer found the first note early Tuesday and reported it to school officials and the Wellesley police, said MassBay spokesman Jeremy Solomon. Police searched the campus and cleared it overnight, he said. However, a second typed note was found at about 2:45 p.m. Tuesday in a bathroom on the Framingham campus, said Framingham Deputy Chief Ron Brandolini. A bomb squad and bomb-sniffing dogs cleared the Framingham campus just after 5 p.m. All classes and activities were expected to resume Wednesday morning, including at the Ashland campus, Solomon said.