"The University is working closely with the student's family and the relevant authorities to solve this problem so that he can join his classmates in the coming days," Harvard spokesman Jason Newton wrote in an e-mail at CNN.
US Customs and Border Patrol confirmed to CNN that Ajjawi had been rejected at the border – but refused any information.
"This person was deemed ineligible for the US based on information discovered during the CBP inspection," the agency said in a statement.
The University newspaper, The Harvard Crimson, describes Ajjawi as a "17-year-old Palestinian residing in Tire, Lebanon."
The Crimson Report cites a written statement by Ajjawi, in which the incoming student describes his meeting with immigration officers at Boston's Logan Airport.
According to Crimson, Ajjawi was held for eight hours before being dismissed. During this time, an immigration officer told him to unlock his phone and laptop and searched it for five hours. The Crimson says he was asked questions about his friends' social media activities.
According to Crimson, Ajjawi was accused of having "political views against the US" voiced by people he follows in social media.
After being questioned, Crimson reports that his visa has been revoked and he was sent back to Lebanon.
The Lebanese Embassy did not immediately respond to a request for comment.
Development Comes Just over a Month After Harvard President Lawrence Bacov wrote an open letter to Secretary of State Michael Pompeo and Acting Homeland Security Secretary Kevin McAleenan, expressing concern over the government's immigration policy and its impact on Harvard academic programs ̵
He criticized the visa and immigration process as "unpredictable and insecure."
Legal representatives for Ajjawi could not be reached immediately for comment, and attempts to directly reach Ajjawi were not immediately successful.