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ISIS: 'A brutally efficient campaign'

The BBC's Paul Wood reports that ISIS Islamist insurgents are "steadily tightening their grip on the north and west of Iraq".

Islamist insurgents in Iraq have seized the city of Tikrit, their second major gain after capturing Mosul on Tuesday, security officials say.

Tikrit, the hometown of former leader Saddam Hussein, lies 150km (95 miles) north of the capital Baghdad.

Iraqi PM Nouri Maliki vowed to fight back against the jihadists and punish those in the security forces who fled offering little or no resistance.

The insurgents are from the Islamic State of Iraq and the Levant (ISIS).

Paul Wood reports.