Google has joined the Technology Coalition and Financial Coalition Against Child Pornography.

The two groups are run by the International Center for Missing and Exploited Children (ICMEC) and its US-focused National Center for Missing and Exploited Children (NCMEC) sister organisation.

Both organisations aim to step up the fight against online child pornography.

The Technology Coalition seeks to improve knowledge sharing between the member companies, and to create law enforcement tools. It will also look into the technologies used by purveyors of child pornography.

The group's members include AOL, Yahoo, Microsoft, EarthLink and United Online.

The Financial Coalition was created last March in an effort to kill the business model behind child pornography websites by blocking access to payment services including credit cards. The group comprises financial institutions and service providers.

"Both coalitions exemplify the best spirit of private industry, as these companies set aside their competitive zeal to work together to protect the world’s most vulnerable citizens," said Ernie Allen, chief executive at NCMEC and ICMEC.

"Google is to be commended for bringing its considerable expertise to the fight."