A Kenyan connected with the Somali-based al-Shabaab militant group was on Wednesday arraigned in a Manhattan court on accusations of training as a pilot in the Philippines and researching on how to hijack planes.

Federal prosecutors charged Cholo Abdi Abdullah with plotting a September 11-style attack on a building in an American city.

The New York Times reports an unsealed federal indictment to describe Abdullah as an operative of al-Shabaab, which is affiliated to Al-Qaeda.

According to the report, the indictment said that under the direction of a senior al-Shabab commander who planned a deadly 2019 attack on a hotel in Nairobi, Kenya, Abdullah sought to obtain pilot training, test flaws in airport security, and take other steps in preparation for hijacking a civil aircraft and conducting a terrorist attack on behalf of the terror group.

He started by enrolling in a flight school in the Philippines in 2016, received training and ultimately completed the tests necessary to obtain his pilot license.

He also researched methods of hijacking a commercial airliner, including ways of breaching a cockpit door from outside.

The indictment added that Abdullah conducted research on the tallest building in a major U.S. city and also sought information about obtaining an American visa. The indictment did not mention the city or building.

The suspect was arrested in the Philippines last year, and was transferred to New York.