Iraqi PM reveals 'ISIL plot to attack West'

Iraq has received "credible" intelligence that the Islamic State of Iraq and Levant (ISIL) group plans to attack subway systems in Paris and in the US, according to Iraq's prime minister.

However, American and French officials say they have no evidence to back up Haider al-Abadi's claim.

Abadi's comments were met with surprise and cautious skepticism by security, intelligence and transit officials in both countries. New York's leaders scrambled to ride the subway to reassure the public the city was safe.

He said his government had received the information on Thursday morning from fighters captured in Iraq and concluded it was credible.

The attacks, he said, were plotted from inside Iraq by "networks" of the ISIL, which controls large areas in Syria and Iraq.

"They plan to have attacks in the metros of Paris and the US," Abadi told a small group of U.S. reporters while in New York for the annual meeting of the U.N. General Assembly.

"I asked for more credible information. I asked for names. I asked for details, for cities, you know, dates. And from the details I have received, yes, it looks credible."

Abadi did not provide any further details, and some Iraqi officials in Baghdad questioned his comments, one telling Reuters that Abadi’s remarks were based on “ancient intelligence” and another calling it “an old story.” Both spoke on condition of anonymity.

Ben Rhodes, a deputy national security adviser to President Barack Obama, said the U.S. had "not confirmed any specific threat."

"What we have consistently said to the Iraqis is if they have information that is relevant to terrorist activity or terrorist plotting, that they can and should share that through our intelligence and law enforcement challenges," said Rhodes, who was travelling with Obama on Air Force One from New York.

"We would certainly take seriously any information they are learning."

French security services also said they had no information confirming Abadi's statement, a French government official said, speaking on condition of anonymity.

New York Governor Andrew Cuomo, New York City Mayor Bill de Blasio and other local officials suggested they were unfazed, updating their public schedules on Thursday to add trips on the city's subway system to reassure millions of daily commuters city which just marked the anniversary of the Sept 11 attacks that launched the U.S.-led global war on terror.

"We are convinced New Yorkers are safe," de Blasio said at a press conference at a lower Manhattan subway station as he stood alongside New York City Police Commissioner Bill Bratton and George Venizelos, assistant director of the Federal Bureau of Investigation.

Bratton said in response to Abadi's comments that he sent more police to patrol subways and streets in the city, which was already on high alert because of the U.N. meeting.

The reports came as French fighter jets struck ISIL targets in Iraq while U.S. warplanes hit them in Syria.

The French strikes were an answer to the beheading of a French tourist in Algeria by fighters, who said the killing was punishment for the French decision last week to become the first European country to join the US-led bombing campaign.

The air strikes carried out over Wednesday and Thursday hit at the small-scale crude refineries that ISIL fighters use to generate well over $1 million in revenues per day.

The strikes by U.S. and Arab warplanes against the oil refineries killed 14 fighters but also left five civilians dead, including a child, according to the Britain-based monitoring group the Syrian Observatory For Human Rights.

The Pentagon said it was aware of reports of civilian casualties, and was investigating, but insisted raids are carried out with precision.

Separately, the FBI said it had identified a fighter with a British accent seen executing Western hostages in ISIL videos.

James Comey, FBI director, said officers had identified the masked man in videos with a knife at the beheading of two American hostages in recent weeks.

"I'm not going to tell you who I believe it is," Comey said. He said he knew the person's nationality, but declined to give further details.

British Foreign Secretary Philip Hammond said earlier in the week that investigators seeking to identify the man were “getting warm.”

Al Jazeera and wire services