A five-year sentence handed to a Bicester magistrate for making bombs to maim and kill has been described as lenient by police.

Det Supt Euan Read said police would ask the Attorney General if there were grounds to appeal the sentence passed on Jonathan Wilkes at Oxford Crown Court yesterday.

Wilkes, 40, who had denied making the explosives to endanger life, was told by Judge Peter Crawford that he lied and lied after the devices were discovered in Oxfordshire woodland.

A jury rejected Wilkes's claims that he intended to kill himself with the devices.

Det Supt Read, who led the 16-strong team of investigating officers, said: "We will speak to the Crown Prosecution Service to see if the Attorney General is in a position to appeal to the Court of Appeal on this sentence."

The court was told the weapons were assembled to target Howard Davies, the boyfriend of Wilkes's former lover, Collette Cooper.

Miss Cooper had ended the affair and had become pregnant by Mr Davies.

Sentencing Wilkes after the nine-day trial, Judge Crawford said: "It is a sad day when a court has to sentence a Justice of the Peace for a crime of this gravity. Nobody who saw the model of the bombs could have failed to shudder at what would have happened to anybody who had been in range if a device had detonated.

"There would have been a rain of nuts which would have killed or injured anybody close by. They were designed to maim and kill. Who was the intended victim, nobody can know for sure. But it is clear if the devices had exploded, the injuries would have been terrible to any person within range."

Judge Crawford added that Wilkes had accused Miss Cooper of being a drug addict in order to "bolster" his story.

Eight bombs were found by a man walking his dog in woodland at Freeland, near Witney, in August, 2000. They were near Wilkes's then home on Wroslyn Road, before he moved to France.

Another bomb was found days earlier on a dry stone wall at Syreford, near Cheltenham.

Wilkes had ordered bomb parts from electrical, plumbing and toy stores by using a mobile phone. He assembled the devices himself.

He claimed he had been targeted by a mystery blackmailer who had ordered him to hand over money and collect the parts.

Wilkes claimed that the man had threatened to expose his affair to his long-term partner Annie Henriot, with whom he has a five-year-old son, Vincent.

But he later changed his story and said he had intended to commit suicide with the weapons but wanted to make it look as if he had been the victim of a bomber.

Wilkes was found guilty of unlawfully possessing eight bombs with intent to endanger life.

He was cleared of the same charge in relation to the Syreford bomb, but was convicted of unlawfully possessing the explosive.

Det Supt Read described Wilkes as "a bomber who was hell-bent on achieving his aim. He seemed to be an individual whose friends and colleagues had no idea what he was up to".

The bombs were much more complex than those used by the IRA, he said. The FBI had even taken an interest in their design.