BNP's mass education affairs assistant secretary Anisur Rahman Talukder Khokon went missing.
He was allegedly picked up by law-enforcers on Monday night, alleged the party and his wife.
Talking to reporters, Khokon's wife Israt Ajmery claimed that members of Rab-3 picked Khokon up from near Ramna Hotel around 10:15pm on Monday and took him to an unknown place.
Israt said as she went to Rab-3 office at Tikatuli, the officials of the elite force denied arresting her husband.
Meanwhile, BNP senior joint secretary general Ruhul Kabir Rizvi at an emergency press conference at BNP chairperson's Gulshan office on Monday midnight said the members of Rab-3 picked Khokon up from Ramna Hotel as he went there to meet some BNP leaders. "We don't know where he was taken by the law enforcers."
UNB said he strongly condemned the incident and demanded the law enforcers present him before people immediately.
Rizvi said people inside Ramna Hotel and pedestrians saw how Rab personnel taking away Khokon in their vehicle.
The BNP leader further alleged that Khokon had been made disappeared by law enforcers in 2015. He was later found in Faridpur after three months.