Forth 2

Pupils have been struck by a mysterious Tourette's-type illness at a school in New York, leaving doctors baffled.

Up to 15 girls at Le Roy High School have developed the ailment over the past few months.

It causes twitching and uncontrollable verbal outbursts - including swearing in some cases.

Doctors say the symptoms could be due to conversion disorder - once known as mass hysteria.

Even though it is a psychological condition, the symptoms are real.

However, campaigner and environmentalist Erin Brockovich is now investigating whether it could have something to do with pollution.

Ms Brockovich - whose life was depicted in a film starring Julia Roberts - is looking into whether a chemical that spilled in a 1970 train derailment about four miles from the school could have anything to do with it.

Although the school has ruled out a link with the derailment because "the plume has been shown moving in the opposite direction some three miles away", it has called in an independent environmental expert to investigate.

The school wants "sound advice" from professionals on the situation, "void of self-interest", school administrator Kim Cox said.

"Our community has suddenly found itself at the centre of national attention due to the students who have been exhibiting neurological symptoms," the school's administrator said in a statement.

"This has led to much speculation, conjecture and misinformation in the national media and consequently within our community."

According to the Mayo Clinic, females are much more likely to get conversion disorder and it is more common in adolescents or young adults.