BAGHDAD (AP) — The Iraqi government launched its biggest push yet to wrest back ground lost to Sunni militants, as soldiers backed by tanks and helicopter gunships began an offensive Saturday to retake the northern city of Tikrit.

There were conflicting reports as to how far the military advanced in its initial thrust toward Tikrit, the hometown of former dictator Saddam Hussein. Residents said militants were still in control of the city by nightfall, while Iraqi officials said troops had reached the outskirts and even pressed deep into the heart of Tikrit itself.