NEW YORK (REUTERS) - The wife of the Afghan-born US citizen charged in last weekend's bombings in New York City and New Jersey has returned to the United States, a law enforcement official said on Thursday (Sept 22), as a defence lawyer pressed to get access to the accused man.

Ahmad Khan Rahami, 28, has been held in a Newark, New Jersey, hospital since being arrested on Monday with wounds after a shootout with police.

Rahami faces federal charges in both states stemming from a Saturday night bombing in Manhattan's Chelsea neighbourhood that injured 31 people and explosives found in two New Jersey locations. No one was killed in the blasts.

Rahami's wife, Asia Bibi Rahami, flew back to the United States overnight, a law enforcement official said. She had voluntarily met with US law enforcement authorities while in the United Arab Emirates this week and gave a statement.

Two years ago when she was pregnant, Rahami had sought the assistance of a US congressman from New Jersey in getting her a visa to allow her to come to the United States from Pakistan.

Rahami and another woman had a child together but had not seen each other in more than two years, the second woman said in a statement reported by ABC News on Thursday.

Rahami had reached out to them just once in the past year, she said.

"I have cooperated with authorities and told them all I know about Ahmad Rahami," said the woman, who was not named in the statement. In court documents filed on Tuesday where she is seeking sole custody of their child, the woman identified herself as Maria Mena.

Authorities have been trying to determine whether Rahami, a naturalised US citizen who emigrated from Afghanistan with his family at the age of seven and lived in Elizabeth, New Jersey, had any assistance in planning the bombings or making the home-made devices.

Rahami was motivated by militant Islamic views, prosecutors said, citing a journal he was carrying when captured in which he begged for martyrdom and expressed outrage at the US "slaughter" of Muslim fighters in Afghanistan, Iraq, Syria and Palestine. The case is being treated by authorities as an act of terrorism.

ACCESS TO A LAWYER

Prosecutors and New York's top federal public defender are squabbling over when Rahami will get a lawyer.

David Patton, the head of the federal public defenders office in New York, asked on Wednesday to be appointed as Rahami's attorney and to be allowed to meet with him, saying the suspect has not had legal advice thus far.

The FBI said Rahami was arrested by police in New Jersey and remained in the custody of that state, not the federal government. A US magistrate judge said late on Wednesday that he accepted that position.

"The government asserts unequivocally that the defendant 'is not in federal custody,'" Judge Gabriel Gorenstein wrote in an order. "Whether there are federal authorities questioning defendant does not address the issue of custody."

The judge said the timetable for when Rahami can meet with a public defender cannot be decided until the issue of custody is resolved.

Normally, a US criminal defendant goes before a magistrate with little delay and, if too poor to afford a lawyer, is appointed a lawyer at that first appearance or soon afterward.

The FBI also continued to search for two men who found a second, unexploded pressure-cooker device that prosecutors say Rahami left in a piece of luggage in Chelsea on Saturday night.

The two men, who took the bag but left the device behind, are not suspects, officials said, but potential witnesses.