Accused letter bomber Guido Amsel took the stand Wednesday in his own attempted murder trial, testifying that he has never sent an explosive to anybody.

The 51-year-old wore a headset and a blue suit as he sat in the witness box with his current wife and other supporters in the courtroom.

Under questioning from his lawyer, he told court that he doesn't have any knowledge in building explosives and that he did not send a pouch, note, or voice recorder to Maria Mitousis in July 2015.

Mitousis, the lawyer for Amsel's ex-wife Iris, was seriously injured when a mail bomb detonated in her hand in July 2015.

Court previously heard Amsel's DNA was found on a pouch in Mitousis' office and on a piece of string following an explosion outside his ex-wife's home in December 2013, where Amsel lived until 2004.

Amsel testified he left string behind on the property when he was designing the driveway and planting trees.

He also told court he spent time in the boardroom of Mitousis' former office in 2011 making photo copies of court documents, and that he has a habit of poking, scratching himself and sweating as he pours over documents.

Amsel has pleaded not guilty to five counts of attempted murder and several explosives-related charges.