The United States Government has raised concerns over the alleged extra-judicial killings, arbitrary arrests and detention of suspected members of the Boko Haram sect by Nigeria's security forces.

The US' observation is coming on the heels of a similar allegation recently made by Amnesty International, which accused Nigerian security agencies of rights abuses.

The US government cautioned Nigerian security agencies against rights abuses in the fight against terror, adding that the international community would not sit idly and watch such breaches.

The Islamic sect, which the military estimates has killed over 3,000 people since it began its insurgency in 2009, also suffered a major setback yesterday as the Joint Task Force (JTF) in Borno State claimed it had killed one Ibn Saleh Ibrahim who allegedly led the attack on one of the nation's civil war heroes, Major General Mohammed Shuwa.

US Assistant Secretary of State in the Bureau of Democracy, Human Rights and Labour, Mr. Michael Posner, raised the issue during a visit to the Minister of Foreign Affairs, Ambassador Olugbenga Ashiru, in Abuja.

Also present at the meeting were the US Deputy Assistant Secretary of State, US Bureau of Democracy, Human Rights and Labour, Ms. Karen Hanrahan, and the country's Ambassador to Nigeria, Mr. Terrence McCulley.

A statement yesterday by the Ministry of Foreign Affairs, quoted Posner as saying that the war against Boko Haram could not be won by sheer force alone.

Terrorism, he said, was a huge and complex challenge but one that demands a rules-based approach to avoid impunity on the part of security and police forces.

Ashiru, however, refuted allegations that Nigeria's security forces and police officers had engaged in extra-judicial killings and arbitrary detention of suspects, adding that the rules of engagement for the security forces in counter-insurgency activities have been in line with international best practices.

Ashiru recalled the recent release of a report by Amnesty International, stating that the report was biased and was not objective, as the Federal Government has initiated a non-violent and multi-faceted approach to stem the tide of terrorism.

This, he said, was in spite of the fact that the terrorists are callous and heinous criminals who indulge in killing innocent citizens and must be tackled head on and kept away in line with due process of law and in the interest of public safety and good order.

The minister also urged Amnesty International not to rely on third party sources in compiling its reports and conclusions, as was apparently done in the recent report on Nigeria.

"It was also for the same reason that representatives of the international body were granted access to some detention centres, including their meetings with the army high command and police authorities during their visit," the statement said.

Ashiru urged members of the US delegation to be more objective in their assessment of the situation, which Nigeria is grappling with, and to offer more support, cooperation and understanding of its counter-terrorism efforts, drawing from their country's experience.

The minister expressed satisfaction at the level of engagement between the two countries through the Bi-National Commission, the statement said.

Meanwhile, the JTF said in a statement in Maiduguri yesterday that it killed Ibrahim during an attack by a combined team of security agents on the sect's stronghold in Maiduguri.

In the statement by its spokesman, Lt. Col. Sagir Musa, the JTF identified Ibrahim as the leader of a group of terrorists that killed Shuwa in Maiduguri on November 2.

Shuwa, a former Minister of Communications, was shot dead during an attack on him and his guests at his Maiduguri home. He was an associate of former Borno State Governor, Senator Ali Modu Sheriff.

However, a few days later, Boko Haram denied involvement in the killing of the retired general.

The sect's spokesman, Abu Mohammed Abdulaziz, told journalists during a teleconference in Maiduguri that it was not involved in his killing, stating that it did not have any problem with the elder statesman.

But the JTF's statement yesterday contradicted the claim by Boko Haram as the task force said Ibrahim had led the assault on Shuwa based on the order of the Islamic sect's leader, Abubakar Shekau.

The statement read: "In a sustained follow up operation this afternoon (yesterday), the combined troops of the JTF Operation Restore Order, 333 Air Defence Regiment, the Department of State Security, supported by Armoured Personnel Carriers and helicopters, conducted a major offensive operation against the insurgent terrorists at Nganaram, Bulabulin and Bayan Quarters areas of Maiduguri metropolis.

"During the offensive and in the counter attack, a major commander of the Boko Haram terrorist sect, commanding the North-west and the North-east of Maiduguri by name Ibn Saleh Ibrahim with some of his commanders and foot soldiers were killed by our operating troops."

Musa said the clampdown was ongoing, adding that Ibrahim was confirmed to be responsible for the assassination of Shuwa.

He said Ibrahim had acted on the orders of Shekau that the civil war hero must be terminated.

Musa said the military was able to recover some weapons, including ammunition and improvised explosive devices during the operation.