Clackamas County investigators studying clues to who strangled a 15-year-old Texas girl in a Milwaukie apartment said there were 55 calls to 9-1-1 dispatchers about that apartment complex in the past year.

Dani "D.J." Countryman was found dead early Saturday morning at the Balboa Apartments after attending a party there the night before. Witnesses told KGW she was seen walking from apartment to apartment, during the party night.

"When I saw her last, she was just happy and having fun," said Malina Cruz.

Some neighbors say the apartment building has been a trouble spot, with neighbors often complaining to police about unruly behavior.

Countryman's sister, Ashley, had a going away party there for D.J. Friday night. The teen was planning to return to Texas Saturday after spending a month in Portland visiting her sister.

Ashley went to apartment 21 just before eight o'clock Saturday morning to wake up D.J. She said D.J. was covered with a blanket and her hand was cold. Medical examiners said she had been strangled

As of Monday there were no suspects or persons of interest in the case, deputies said. Detectives were interviewing neighbors and asked some partygoers for permission to swab for DNA evidence.

"It's unbelievable the way someone could treat life like it was garbage and toss it away like it was nothing," said Rick Sprayberry, Ashely's boyfriend. Sprayberry lives in the apartment upstairs.

Dani Countrymen was found strangled after a party in Milwaukie.

Outside the apartment, a memorial continued to grow.