MARJAH, Afghanistan (AP) – Sniper teams attacked U.S. Marines and Afghan troops across the Taliban haven of Marjah, as several gun battles erupted Monday on the third day of a major offensive to seize the extremists' southern heartland.

Multiple firefights broke out in different neighborhoods as American and Afghan forces worked to clear out pockets of insurgents and push slowly beyond parts of the town they have claimed. With gunfire coming from several directions all day long, troops managed to advance only 500 yards (meters) deeper as they fought off small squads of Taliban snipers.
The massive offensive in the Marjah area — the largest Taliban stronghold and a key opium trafficking hub — involves about 15,000 U.S., Afghan and British troops and is the biggest joint operation since the 2001 U.S.-led invasion of Afghanistan.
Claiming optimism on the offensive, also known as Operation Mushtarak (Together), Afghan military official, Brig. Gen. Sher Mohammad Zazai said Monday that most of the militants have started fleeing south and that only three Afghan troops had been injured.
The mission faced a setback on Sunday when two U.S. rockets slammed into a home outside Marjah, killing 12 civilians. NATO said Monday that the rockets missed their target by about 600 meters, or about a third of a mile. NATO had earlier said the rockets missed their target by just 300 meters.
Six children were among the dead from the rocket strike, a NATO military official confirmed Monday, speaking on condition of anonymity because the information had not been formally released.
The top NATO commander in Afghanistan, Gen. Stanley McChrystal, apologized for ""this tragic loss of life"" and suspended use of the sophisticated rocket system pending a thorough review.
Inside Marjah, sporadic firefights increased by midday. One armored column came under fire from at least three separate sniper teams, slowing its progress. One of the teams came within 155 feet (50 meters) and started firing.
Marines said their ability to fight back has been tightly constrained by strict new rules of engagement that make their job more difficult and dangerous. Under the rules, troops cannot fire at people unless they commit a hostile act or show hostile intent.
""I understand the reason behind it, but it's so hard to fight a war like this,"" said Lance Corp. Travis Anderson, 20, from Altoona, Iowa. ""They're using our rules of engagement against us,"" he said, stating that his platoon had repeatedly seen men dropping their guns into ditches before walking away to melt among civilians.
Allied officials have reported two coalition deaths so far — one American and one Briton killed Saturday. Afghan officials said at least 27 insurgents have been killed in the offensive.
Separately in southern Afghanistan, NATO said two service members died Sunday — one from small-arms fire and the other from a roadside bomb explosion. Both were British, according to the British government.