An ex-chairman of the Joint Chiefs of Staff was summoned Tuesday for questioning over his alleged involvement in the selection of a defense firm to build military helicopters in exchange for kickbacks.
  

Retired Adm. Choi Yoon-hee appeared before the Seoul Central District Prosecutors' Office in southern Seoul. 
  

The 62-year-old is suspected of receiving bribes in the process of picking the Anglo-Italian AW159 Wildcat as the country's new multi-mission maritime helicopter, according to prosecutors. Choi was the Navy chief of staff when the Wildcat, which does not meet the required operational capabilities for the Navy, was selected in 2012.
  

So far, seven current and former military officials have been indicted on charges of making bogus reports on the helicopter's capability.
  

During the prosecutors' investigation, one of the defendants has stated that it was all done under the direction of Choi.
  

Choi's son has been investigated for allegedly receiving 20 million won ($17,200) from an arms broker, identified only by his surname Ham, and repaying 15 million won. He denied any involvement by his father in the transaction, saying it was done individually, according to the prosecutors.
  

The prosecutors said Tuesday's questioning will be focused on whether Choi was involved in selecting the Wildcat and if there were any unlawful underhand dealings in the process. 
  

"I will sincerely answer (the questions) during the investigation," Choi Yun-hee told reporters before entering the prosecutors' office.
  

The summons is part of the prosecution's investigation into widespread corruption in the defense industry.
  

A special investigation team -- comprised of government, military and prosecution officials -- was formed to crack down on corruption in the defense industry after a series of shady deals came to light over the past year. (Yonhap)