The Sabres are "very concerned" for forward Kyle Okposo, who is hospitalized and in intensive care with an undisclosed ailment.

WGR-AM 550 in Buffalo first reported Tuesday Okposo "has been in the hospital undergoing multiple tests" to determine the cause of an illness he's been dealing with since March 28. Okposo is in in-patient care in the Neuro Surgical ICU at Buffalo General Hospital, The Buffalo News confirmed.

Sabres coach Dan Bylsma offered few details, including a diagnosis, while meeting with reporters Wednesday following the team's morning skate.

"It’s a difficult thing for him to be dealing with now in this situation," Bylsma said. "Very, as a coach and a person, concerned for him and his situation.

"He’s seeing our doctors and done some tests."

The Sabres later said in a statement that Okposo was under the care of team doctors "as he deals with symptoms of an illness."

"Out of respect to Kyle and his family, we will have no further comment at this time," the team said.

Okposo, 28, last played March 27 vs. the Panthers — his second game since returning from a seemingly unrelated rib injury. The NHL veteran, who signed with the Sabres as a free agent this offseason, originally started feeling ill during the game, which was played in Buffalo, and has not practiced with the team since.

He was not in the lineup for Buffalo's game Wednesday night and has been ruled out for the team's remaining two games this season.

"He’s sick and ill," Bylsma said. "(I'm) very concerned."