The European Commission said Tuesday it was probing computer and television monitor makers from outside the European Union for a possible cartel.

Without naming the companies targeted by the investigation, the EU competition watchdog said that it had sent formal information requests to "a number" of companies.

The firms make thin film transistor and liquid crystal displays for computers, televisions and hand-held devices such as mobile phones and digital cameras.

"The purpose of this investigation is to ascertain whether there is evidence of a cartel agreement and related practices concerning price fixing," the commission said in a statement.

The EU's executive arm said that no raids had been conducted in the case because the companies operated from abroad although it was in contact with the appropriate authorities.