HAGERSTOWN, Md. (AP) — Family members of an American development expert kidnapped in Pakistan by al-Qaeda more than two years ago said Thursday that a recently released video and letter haven’t convinced them he’s alive.

Warren Weinstein’s wife, two daughters, son-in-law and grandchildren released a statement asking for “date-specific” confirmation that the 72-year-old Rockville resident is alive and well.

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“We are extremely concerned about his health and implore his captors to attend to his medical needs. More importantly, we ask that they find it in their hearts to release him immediately so he may return home to us for the additional urgent care he needs,” the family statement read.

Weinstein appeared in a video sent last week to reporters in Pakistan, appealing to President Barack Obama to negotiate his release. It was the first video to show Weinstein since September 2012. There was no indication of when it was made.

An accompanying, handwritten note was dated Oct. 3.

The family statement didn’t specify Weinstein’s medical needs. His employer, J.E. Austin Associates, has said Weinstein needs medication used for treating heart problems.

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The statement said family members “have been told the U.S. government is doing what it can to assist in his return, but are not aware of what those efforts are to date.”

The White House has called for Weinstein’s immediate release but has said it won’t negotiate with al-Qaeda.  The State Department said Monday that officials were actively working with Pakistani authorities to try to secure his release.

Weinstein’s family also expressed gratitude for the efforts of Rep. John Delaney, D-Md., whose district includes Rockville.

Delaney said in a statement he has given the family his personal assurance that he will continue to press for Weinstein’s release.

“Warren Weinstein is an American being held captive by our enemies and this singular fact cannot be forgotten, overlooked, or marginalized. We must be relentless in our efforts to bring him home and we must maintain a sense of outrage and determination,” Delaney said.

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