Ethiopian Prime Minister Meles Zenawi  claims "terrorists" are using political party memberships as a disguise [Reuters]

Ethiopian authorities have arrested 29 people for plotting to carry out bomb attacks and for being members of a rebel group, a government spokesman said.

The police had "solid evidence" to make these arrests on "suspicion of plotting to commit criminal acts contrary to anti-terrorism legislation," Shimeles Kemal said on Monday.

Suspects were detained on August 28 on charges of colluding with the Eritrea-based rebel group Oromo Liberation Front (OLF) to plant explosives and conduct bomb-training courses, Kemal said.

The spokesman claimed the suspects were members of the OLF group, which Ethiopia lists as a terrorist organisation.

Nine of the detained are members of two prominent opposition parties, Demelash Woldemikael, deputy commissioner of federal police, told the Reuters news agency.

Ethiopia has been accused of cracking down on opposition campaigners from the Oromo ethnic group, the Horn of Africa nation's biggest with 27 million people out of a population of 80 million.

Rights groups have criticised Meles Zenawi, the Ethiopian prime minister, for crushing dissent.

Government 'fabrications'

Meles says "terrorists" are using political party membership to hide their activities.

Opposition politicians dismissed the charges, saying that the government is "well-known for its fabrications".

"[The government doesn't] want to know the facts, so they come up with their lies," said Andualem Arage, a senior member of the opposition Medrek coalition.

"They are doing this to prevent people from standing up for their rights," Arage added, claiming the government is fearful Arab Spring-type protests could erupt in Ethiopia.

Demelash denied any political motives behind the 29 arrests.

"Their political activity had nothing to do with their incarceration," he said.

"They were posing as peaceful activists but were in fact operating with the OLF, which is responsible for past killings of innocent civilians."