Baghdad, Iraq ? An outraged Iraqi National Assembly demanded an apology from the U.S. government Tuesday for the rough treatment one assembly member said he received from an American soldier at a military checkpoint.

The rhetorical confrontation is another sign that relations between the two countries are trickier now that Iraq has a government of elected representatives who aren’t necessarily favored or influenced by U.S. authorities or interests.

The 275-member assembly, which must pick government ministers and write a constitution, spent much of Tuesday expressing outrage about Fattah al-Sheikh’s allegation and debating what demands to make of the U.S. government to redress the offense.

Al-Sheikh was shaken and crying as he struggled to tell the assembly that a U.S. soldier had manhandled him. The incident occurred at a checkpoint leading into the heavily fortified Green Zone, the central Baghdad compound where the assembly meets, he said.

“I was dragged to the ground,” said al-Sheikh, a member of a small party sympathetic to rebel Shiite Muslim cleric Muqtada al-Sadr. “There were cars beside mine at the checkpoint, but I was the only one who paid this price.”

Al-Sheikh and witnesses said a soldier kicked his car, pulled him from the vehicle, grabbed him by the neck and handcuffed him. When he protested that he was a member of the assembly, a soldier scoffed at the group, al-Sheikh said.

The account ignited condemnations from a cross-section of the assembly.

Iraqi lawmaker Fattah al-Sheikh walks to his seat after addressing the National Assembly in Baghdad, Iraq. Al-Sheik said Tuesday that he was mistreated by an American soldier at a U.S. checkpoint outside the heavily fortified Green Zone, where parliament meets in central Baghdad.

“Let’s ask ourselves,” said Falah Shnaishel, of the United Iraqi Alliance, which won the largest number of seats in the Jan. 30 election. “Is this the democracy we’ve been hoping for?”

The U.S. military said it was investigating the allegation. Meanwhile, Maj. Gen. William Webster, the commander of U.S. troops in Baghdad, “expressed his regret over the incident.”