A 10-year-old girl’s leg swelled three times its normal size and turned black after she accidentally stepped on a poisonous adder snake, London’s Daily Mail reported Tuesday.

Mollie Hawker, of Poole, England, was walking in a nature reserve with her mother, Karen, and brother, Ellis, 2, when the incident happened.

“Suddenly I heard Mollie scream and as I turned around, she flicked off her flip-flop,” Karen Hawker told the Daily Mail. “I looked down and saw a brown snake lying on the path. I saw she had two tiny puncture marks in her big toe, but tried to calm her down as she was panicking.”

Hawker said Mollie’s leg turned from red to black to purple as she was admitted to Poole Hospital in England, where she spent six days.

“Mollie’s was one of the worst cases that I have seen,” said Dr. Antoinette McAulay, a consultant pediatrician at Poole Hospital. “She was in a lot of pain. We gave her antibiotics and minor surgery to the area around the toe to break down the swelling.”

Click here to read the full story from the Daily Mail and to see pictures of Mollie’s bite.