WASHINGTON — The Iraqi general in charge of the Baghdad security plan and the Interior Ministry is pressing Prime Minister al-Maliki to lift legal immunity for 15 Sunni members of parliament and begin prosecuting the lawmakers for conspiring with terrorists, in some cases Al Qaeda.

On April 18, Lieutenant General Aboud Qanbar presented the Iraqi premier with CD-ROM dossiers for the Sunni politicians, including almost all members of the National Dialogue Front, a bloc of three parties that have sought to negotiate cease-fires with those remaining portions of the Sunni Arab insurgency that have not been subsumed by Al Qaeda. The discs on Mr. Maliki’s desk include photographs, testimony, and transcripts of conversations as part of the evidence against the premier’s political opposition.

The lawmakers’ recommendations for prosecution include some American allies such as Adnan al-Duleymi, whom American officials say is likely not linked to terrorism. But they also include parliamentarians that the American military leadership believes are senior terrorist operatives, such as Khalaf al-Ayan.

An American military official this week confirmed to The New York Sun that on April 3, American forces raided Mr. Ayan’s house in Yarmouk and found stores of TNT that matched the kind used in the suicide belt that detonated on April 12 at the Iraqi parliament’s cafeteria. That blast killed a member of parliament, Mohammed Awad, a Sunni Arab member of Mr. Ayan’s Dialogue Front, yet the terrorist who killed him is believed to have been a member of Awad’s security detail.

But the background on Mr. Ayan, who has threatened to return to “resistance” if the political process does not yield to the demands of his Sunni constituency, also implicates him in a string of attacks in Mosul on May 17 that detonated bridges and blew up a police station, according to one senior Iraqi Sunni official and an American intelligence officer who asked not to be named because of the sensitivity of the investigation. A raid last week on his parliamentary offices, in which American forces participated, yielded time-stamped before-and-after photos of the attacks, according to these sources.

Al Qaeda in Iraq claimed credit for the May 17 attacks, as it did for the parliament bombing. Mr. Ayan is believed to be the political leader of a rival of that group, the Islamic Army of Iraq, suggesting that the two organizations are cooperating. “The Islamic Army of Iraq coordinates attacks with Al Qaeda,” the senior Iraqi official said. “The insurgency has consolidated.”

The suspect list of members of parliament is a particularly sensitive matter for Washington, which is seeking both to purge sectarian ministers and officials from the Iraqi government and promote reconciliation between the Shiites and the Sunnis.

A long-standing complaint for American military officers is that General Aboud has issued target lists to his officers in the Iraqi army that consist only of Sunni suspects and not Shiite death squads, as the Sun first reported on May 3. American commanders in Iraq have shared, for example, information on Shiite legislators, such as a former national security minister under Prime Minister Jafari, Abdul Karim al-Eaneze. But the list of legislators recommended for prosecution includes only Sunnis.

Further complicating the situation is that Mr. Ayan, as well as other members of parliament recommended for prosecution, such as Mohammed al-Daini and Saleh al-Mutlak, is pushing for legislation asking American soldiers to leave Iraq. Last week Mr. Daini was in Washington meeting with members of the press and Congress, voicing his desire for the Americans to leave and promising that the withdrawal of American troops would not precipitate a civil war or more violence.

Yesterday, another American official familiar with the prosecution list conceded that only a few of the legislators were tied in a serious way to terrorism. This source explained that members of personal security details for legislators had been detained in some cases and suspected of links to militias and insurgents for both Sunni and Shiite legislators, but that this alone did not prove much. “Only a handful of these guys on Maliki’s desk are plotting operations,” he said. For this official however, Mr. Ayan is one of those members of parliament who should be prosecuted.

Mr. Ayan himself has been an outspoken critic of the American military presence in his country. A former Baathist who participated in the December 2005 elections after much persuading from the American Embassy, he has since opposed the Baghdad security plan.

On January 10, Mr. Ayan appeared on Al-Jazeera and appealed to the United Nations to end the American and Iraqi offensive that drove out Sunni terrorists from Baghdad’s Haifa Street. The offensive was widely seen by American soldiers five months later as the first step toward the revival of the neighborhood, which had seen spiraling executions and most of its residents driven out.