Rescue workers trekked overnight across a remote mountain forest carrying a woman who had survived a crash that killed five of the six people aboard.

SAN JOSE, Costa Rica -- The sole survivor of a plane crash near Costa Rica’s capital, in which five other people died, is in serious condition in a hospital, the local Red Cross said on Tuesday. The 31-year-old woman was one of six people on board the small aircraft when it crashed southeast of San Jose.

A small plane traveling to Costa Rica's capital of San Jose crashed on Monday afternoon, authorities said, killing five of the six passengers on board.

Cordero said it took at least another five hours to remove the remaining bodies from the crash site, according to the Times. The victims who died were between the ages of 27 and 62, per the AP. An investigation into the crash is ongoing. The Red Cross did not immediately respond to PEOPLE’s request for comment.

The small plane went down in a mountainous area on the outskirts of the Costa Rican capital, San Jose. One of the six people on board is in a critical condition.