Police officers stand guard at the site of the Itaewon crowd crush, in this Nov. 1 photo. Yonhap

A special investigation team raided a hotel adjoining the site of the deadly Itaewon crowd crush and two other locations Wednesday over suspicions that its illegally extended structures made the narrow place even narrower, officials said.

The investigation team sent 14 investigators to Hamilton Hotel, the home of the hotel's head and another location to seize documents on hotel management and administrative licenses, the officials said.

The hotel's building ledger showed it illegally extended a 17.2-square-meter terrace on its northern side of the main building and installed other illegal structures.

At least 156 people, mostly in their 20s, were killed in the Oct. 29 crowd crush on a downhill alley that runs along the side of the outer wall of Hamilton Hotel. News media and critics have pointed out the hotel's extended structures may have made the narrow alley even narrower.