"Two scientists were injured outside Monterrey Technological Institute's campus in the State of Mexico on the outskirts of the capital. One of the boffins was involved in robotics research. Mexico State Attorney General Alfredo Castillo said at a news conference that the group's involvement was identified from a partially destroyed note found at the scene. The group opposes experiments with nanotechnology and has staged attacks on academics before. It has been linked to attacks in several different countries of Europe, including Spain and France."

Advertisements on government radio and television have been urging Mexicans for weeks to register their cellphones by sending their personal details as a text message, but on Thursday 30 million lines remained unregistered as the Saturday deadline neared.

Analysts said that any related losses for Mexico's largest wireless operator, America Movil, would be tiny relative to the company's overall sales.