What is Islam's Gülen Movement?

Founder Fethullah Gülen: His motives have been questioned in the past.

Turkey's Gulen movement, which promotes service to the common good, may have grown into the world's biggest Muslim network. Is it the modern face of Islam, or are there more sinister undercurrents?

From Kenya to Kazakhstan, a new Islamic network is attracting millions of followers - and billions of dollars.

Inspired by a little-known Turkish imam, the Gulen movement is linked to more than 1,000 schools in 130 countries as well as think tanks, newspapers, TV and radio stations, universities - and even a bank.

This massive network is unlike anything else. It has no formal structure, no visible organisation and no official membership.

Its supporters say they simply work together, in a loosely affiliated alliance inspired by the message of charismatic preacher Fethullah Gulen, who promotes a tolerant Islam which emphasises altruism, hard work and education.

Turkish businessmen are attracted by what they see as his international outlook and pragmatic approach to issues like using credit.