Harbhajan becomes the sixth player reported to the ICC this year

Umpires reported Harbhajan to the International Cricket Council after watching his action during the second Test against Bangladesh in Chittagong.

This is the second time he has been through the bowling review process.

The doosra is the off-spinner's secret weapon, a delivery spinning away rather than into the right-handed batsman.

It is the same delivery that forced Sri Lanka's Muttiah Muralitharan to be sent for remedial work.

ICC chief executive Malcolm Speed said: "Harbhajan Singh will now work with an expert team over the next six weeks to address these concerns. He can continue to play international cricket and cannot be reported again during this period.

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"At the end of that time the ICC will be provided with a specialist report on the remedial action, if any is required, that has taken place."

Harbhajan becomes the sixth player reported to the ICC under its revised process to deal with potentially flawed actions in 2004.

Shabbir Ahmed (Pakistan), Muralitharan, Blessing Mahwire (Zimbabwe) and Abdur Razzaq (Bangladesh) have all had their actions reviewed and undergone remedial work this year.

A report on the action of Shoaib Malik (Pakistan) is due to be received by the ICC later this week.

The previous occasion that Harbhajan's action came under review was in November 1998 when he underwent remedial work in London.