New Delhi, June 13 -- A London judge sentenced four Palestine Action activists to several years in prison Friday for acting as terrorists when they raided an Israeli defense factory in the U.K. and smashed equipment with the intent of disrupting production of weapons they feared would kill people in Gaza.

The break-in at Elbit Systems caused 1.2 million pounds ($1.6 million) in damage and led to a clash with security guards and law enforcement that left a police officer with broken back.

Justice Jeremy Johnson ruled that the crime went beyond the criminal damage convictions of the four because they aimed to stop the defense company from operating or force the British government to stop its production, which he said gave the crime a "ter...