A Chinese woman trapped in a locked room for 30 hours has been saved in the most unlikeliest of ways.

According to a local government statement, the woman, only identified as Zhou, was saved by police after she hurled a pillow bearing a message written in her own blood out of a window.

So what happened?

Zhou was cleaning a guesthouse in Sichuan Province, western China, and in what was a very bad coincident, she entered the bedroom without her phone. After cleaning the bedroom, Zhou tried opening the door, and that is when reality dawned on her.

For one-and-a-hald days, Zhou tried in desperation to open the door from the inside but she could not because of a malfunctioning lock. All this hours, Zhou had no access to food, not even a toilet was in the room that was on the sixth floor of the building.

“After many failed attempts to save herself, and out of desperation, she bit her finger and used the blood to write ‘110 625’ on a pillow which she then threw out the window,” a social media account owned by the local government in Sichuan’s Leshan City said.

110 is the emergency services phone number in China, while 625 was the number of the room she was tapped in.

Fortunately for her, a delivery guy, Zhang Kun, spotted the message on the pilow and immediately informed the police.

“I was pretty scared, but when I saw the number ‘110‘ on the pillow, I realised this might be a distress call,” Zhang said in the local government statement, as reported by AFP.

In videos published by local media, a scruffy Zhou can be heard thanking the police after they kicked the door open for her. “I went in there yesterday morning and it’s been one day and one night,” Zhou says.

In the end, the woman was rescued, while Zhang was awarded 3,000 yuan (KSh54,000) by the authorities in Leshan for his role in the rescue.