Staff at the University of Maryland in the US are investigating claims that students used text messages to cheat in exams.

According to the Washington Post, more than a dozen students are being investigated for using mobile phones to receive the answers in exams.

The students are accused of receiving text messages from friends who had access to answer keys for the tests.

The university acknowledged that it had problems with students storing answers in high-end calculators but claimed it had never occurred to staff that students could use mobile phones to cheat.

Claims that students exploited a common practice whereby professors post answer keys outside their offices after an exam so that students can immediately calculate how they did are being looked into.

Preliminary investigations suggest that students arranged to have friends outside the classroom to check the answers and send them via text message.

Other professors posted answers on their websites, and students may have surfed the sites using phones equipped with web browsers to cheat while still in the exam room.