Sen. John Fetterman, D-Pa., «will be back soon,» his chief of staff he tweeted on mondayposting the first photos of the senator since he was voluntarily hospitalized for clinical depression nearly three weeks ago.

The photos showed Fetterman and his chief of staff, Adam Jentleson, huddled over papers in an apparent discussion. Jentleson wrote in a tweet that the two discussed rail safety legislation, the Farm Bill and other Senate business. Last week, Fetterman cosponsored a rail safety bill while receiving hospital care.

«John is well on his way to recovery and I wanted him to say how grateful he is for all the well wishes,» Jentleson wrote, adding that the senator was «laser focused» on Pennsylvania and would «be back soon.»

Fetterman checked into Walter Reed National Military Medical Center last month on the recommendation of Brian Monahan, a congressional assistant physician. At the time, a senior aide said Fetterman would most likely stay in the hospital for «a few weeks» while doctors tried different medications and adjusted the dosage. The senator had been having trouble adjusting to his new reality after the stroke and had been navigating questions about his self-esteem, the aide said at the time.

Fetterman suffered a stroke last year before winning the Pennsylvania Senate race. Depression is common after a stroke, according to the American Stroke Association. It can be caused by chemical changes in the brain that make it difficult to feel positive emotions, or by a psychological response to the stress of the event.

The senator’s office has so far not released any concrete information on when he will return to the Senate, where Democrats hold a 51-49 majority. Last week, Fetterman’s spokesman, Joe Calvello, said in a statement that the legislator was «on the road to recovery» and was visiting staff and family daily.