“The sentences are null and void,” al-Wefaq said in a statement on Monday, stressing that they were based on false accusations and forced confessions.
It came after a High Military Court in Bahrain earlier on Monday sentenced six people to death over alleged involvement in terror acts.
“The political authority has proven it is not qualified to rule the country due to its punitive and reckless policies,” the statement by the opposition group added, al-Manar reported.
Al-Wefaq further called on the international community to “bear its historical responsibility and save the Bahraini majority which has been oppressed” by the ruling regime.
The military court also convicted and sentenced seven defendants to seven years' incarceration and stripped their Bahraini nationality, and acquitted five others.
Recently, al-Wefaq released a statement slamming military trials of civilians as a violation of both domestic and international laws.
On March 5, Bahrain approved the trial of civilians at military tribunals in a measure blasted by human rights campaigners as being tantamount to imposition of an undeclared martial law countrywide.