A U.S. appeals court says the 17-year prison sentence imposed on convicted terrorism plotter Jose Padilla was far “too lenient.” The court also ordered a new hearing to determine what it calls a more appropriate punishment.

The three-judge panel ruled Monday that Padilla got off “too lightly” for someone who trained to kill at an al-Qaida camp and also has a long, violent criminal history.

Padilla, a former Chicago gang member and Muslim convert, was convicted in 2007 of aiding a US-based al-Qaida cell that supplied recruits and funding to Islamic extremists abroad. Two other co-conspirators were also convicted. The appeals ruling upheld all the convictions.

The judges ruled that Padilla posed “a heightened risk of future dangerousness” because of this training at an al-Qaida camp in Afghanistan.

Padilla was initially suspected of plotting to detonate a radioactive “dirty bomb” in the United States, but his eventual indictment did not mention that allegation.