BAGHDAD (Reuters) - Former Iraqi Deputy Prime Minister Tareq Aziz was jailed for 15 years on Wednesday and two of Saddam Hussein's half brothers were sentenced to death for their roles in the killings of dozens of traders in 1992.

The traders were executed after being accused of hiking prices of goods in breach of state price controls, when Iraq's economy was collapsing as a result of U.N. sanctions imposed for its 1990 invasion of Kuwait.

The court has ruled that Watban Ibrahim al-Hassan ... and Sabaawi Ibrahim al-Hassan be hanged until death for committing a premeditated killing ... a crime against humanity, Judge Raouf Abdul Rahman said.

The verdict came less than two weeks after the same Iraqi High Tribunal cleared Aziz, for years the public face of Saddam's regime, of any role in killing and displacing Shi'ite Muslims in 1999. That trial saw Saddam's cousin, Ali Hassan al-Majeed, receive a third death sentence.

Majeed, nicknamed Chemical Ali for his use of poison gas to kill Kurdish villagers in the 1980s, was also sentenced in the trader case to 15 years.

Saddam's secretary Abed Hamid Mahmoud, already jailed for life in another case, received a second life sentence.

A senior member of Saddam's Baath party, Mizban Hadi, was given 15 years in prison and the former head of Saddam's presidential office, Ahmed Hussein Khudhayer, got six years. A former central bank governor, Isam Rasheed, was acquitted.

The Iraqi High Tribunal was set up after the 2003 U.S.-led invasion to try former members of Saddam's government, including the leader himself.

New York-based Human Rights Watch estimates 290,000 people vanished under Saddam, many of their bodies heaped in ditches.

Saddam was executed in December 2006 after being convicted of crimes against humanity for the killing of 148 Shi'ite men and boys after a 1982 assassination attempt.

(Writing by Tim Cocks; Editing by Dominic Evans)