Camp Springs, Maryland - An investigation is underway after multiple people fell ill in connection to a suspicious package delivered on Thursday to a military base near Washington.

Joint Base Andrews confirmed in a statement that parts of the Maryland site were evacuated after the "suspicious" package was opened. The base is used regularly for presidential flights.

"As a precaution, the building and connecting building were evacuated," the statement said, according to CNN.

"Joint Base Andrews first responders were dispatched to the scene, determined there were no immediate threats, and have turned the scene over to (the) Office of Special Investigations," it said.

According to Axios, a military spokesperson said in a statement that "multiple individuals felt ill" after the package was opened and received treatment before being released.

A Joint Base Andrews spokesperson did not respond immediately to AFP's request for confirmation of the incident.

CNN, citing two unidentified sources, said the package contained an "unknown" white powder and "political propaganda" that were being assessed by investigators.

The base is a short drive from DC and is often used for flights by senior government officials.

President Donald Trump landed at the facility as recently as Wednesday on an Air Force One flight returning him from a business forum in Florida.