A Japanese national and 10 Filipino employees of a technology firm operating in the suburban Philippine city of Makati have been arrested for illegally "cracking" mobile phone SIM cards to obtain free calls and Internet services, local police said Tuesday.

The Philippine National Police Anti-Cybercrime Group said Yusuke Otani, 32, a Japanese national, and 10 local employees of Tech Resource Inc. were apprehended during a raid at their office in Makati on Monday.

The arrests were made on the strength of a search warrant relating to 170 alleged violations of the country's cybercrime laws.