AUSTIN, Texas (NewsNation) — The woman accused of killing cyclist Anna Moriah “Mo” Wilson and fleeing to Costa Rica attempted to hide her identity with fake names and by changing her appearance, U.S. Marshals said Thursday.

Kaitlin Armstrong, 34, was arrested at a hostel on Santa Teresa Beach in Provincia de Puntarenas, the Marshals Service said in a statement.

When she was arrested, U.S. Marshals said her appearance had changed, with her hair being chopped down to shoulder-length and dyed brown. Her nose was changed. She told authorities the change was from a “surfing accident,” Marshals said.

Wilson, 25, was found dead May 11, and Austin police on May 19 issued a murder warrant for Armstrong.

Authorities said Armstrong sold her vehicle May 13, then flew from Austin to Houston shortly after being questioned that day by authorities about Wilson’s death. She then flew to New York before using a fraudulent passport to fly from Newark, New Jersey, to San Jose, Costa Rica, on May 18, the service said.

Wilson, a competitive gravel and mountain bike racer and Vermont native known as “Mo,” had been in Austin for a cycling event. According to an affidavit, Wilson had previously dated Armstrong’s boyfriend, cyclist Colin Strickland, who has cooperated with investigators and is not a suspect.

The Associated Press and NewsNation affiliate KXAN contributed to this report.