* Jaser to return for bail hearing
* Lawyer says will "defend himself vigorously"
* Iran reacts angrily to reported links to case
By Allison Martell and Randall Palmer
TORONTO/MONTREAL, April 23 (Reuters) - Two men charged in Canada with plotting an attack on a passenger train appeared in separate courts on Tuesday while Iran reacted angrily to police accusations that the plotters were backed by al Qaeda elements in Iran.
Raed Jaser, 35, of Toronto and Chiheb Esseghaier, 30, of Montreal were arrested in separate raids and charged on Monday, sparking worries of a Canadian attack just one week after the Boston Marathon bombings killed three people and injured more than 200.
Jaser arrived at the procedural hearing in Toronto's Old City Hall courthouse sporting a long black beard and black cap. Details of the hearing are covered by a publication ban.
Jaser, who denied an involvement, was detained and will return for a bail hearing at a later date, his lawyer, John Norris, told reporters.
"He denies the allegations and he will vigorously defend them," Norris said outside the court, describing Jaser as being in a state of "shock and disbelief."
He would not disclose Jaser's nationality but said he has been a resident of Canada for 20 years.
Outside the court room, a middle-aged man, a woman in a cream-colored hijab and a younger man identified themselves as family, but would not give their names or answer questions.
Esseghaier, a Tunisian-born doctoral student at a Montreal-area university, appeared at a Montreal court, handcuffed and in shackles.
He told the judge that conclusions had been drawn from deeds and words "that are only appearances."
"We can't conclude -" he said before being cut off by Quebec judge Pierre Labelle, who said this appearance was only designed to fulfill a legal requirement that he appear in his province within 24 hours of his arrest.
Bearded and bespectacled, Esseghaier was remanded in custody until an arrest warrant is executed and endorsed in Quebec. Federal prosecutor Richard Roy said he expected this to happen Tuesday, allowing Esseghaier to be flown back to Toronto for a court appearance there.
Canadian authorities have linked the two to al Qaeda factions in Iran but they say there is no indication that the attack plans, which police described as the first known al Qaeda-backed plot on Canadian soil, were state-sponsored.
Police said they had been investigating the two suspects since last fall after a tip from the Muslim community in Toronto.
U.S. officials said the attack would have targeted a rail line between New York and Toronto, a route that travels along the Hudson Valley into New York wine country and enters Canada near Niagara Falls.
Canadian police said only that the plot involved a passenger train route in the Toronto area.
Little is known about Jaser but a spokeswoman for the Institut National de la Recherche Scientifique near Montreal confirmed to Reuters that Esseghaier was a doctoral student at the research institute.
Iran had some senior al Qaeda figures under a form of house arrest in the years following the Sept. 11, 2001, attacks, but there has been little to no evidence to date of joint attempts to execute violence against the West.
However, a U.S. government source said Iran is home to a little-known network of alleged al Qaeda fixers and "facilitators" based in the city of Zahedan, very close to Iran's borders with both Pakistan and Afghanistan.
Iran reacted angrily to being tied to the arrests. Canada last year severed diplomatic ties over what it said was Iran's support for terrorist groups, as well as its nuclear programmed and its hostility towards Israel.
"No shred of evidence regarding those who've been arrested and stand accused has been provided," Iranian Foreign Minister spokesman Ramin Mehmanparast said, according to the Mehr news agency.