The GOP lawmaker has missed about 50 roll call votes, and colleagues have not heard from him, Politico reports.

Rep. Tom Kean Jr. (R-N.J.) has vanished from Capitol Hill, and colleagues have not heard from the two-term congressman who lasted voted on March 5, Politico reported Wednesday.

Kean’s team told the outlet he has unspecified health issues, but even fellow Republicans in the New Jersey delegation have been unable to reach him, the outlet noted.

GOP Reps. Jeff Van Drew and Chris Smith have reached out to Kean to check on his welfare, only to be met with “radio silence,” Van Drew said. Ditto for Republicans in the New York delegation, Politico wrote.