* More than 30 arrested following attack
* Still not clear who was behind the incident
KINSHASA, Feb 28 (Reuters) - Democratic Republic of Congo has arrested more than 30 people after a group of armed men attacked the residence of President Joseph Kabila in a suspected coup bid, authorities said on Monday.
Information Minister Lambert Mende said seven people were killed during the fighting that followed Sunday's attack on Kabila's Kinshasa residence, up from an initial toll of six.
Mende said around sixty men armed with light weapons, rocket propelled grenades and machetes attempted to break into Kabila's house but were repelled by the Republican Guard, one of whom was seriously injured. Fighting then spread to a nearby army base before calm was restored.
"At the moment we have no idea (why this happened) but there are lots of rumours," Mende said in an interview, adding it was not clear whether there was foreign involvement.
Mende said some of the attackers appeared to have military training but he denied suggestions that the attack had been carried out by members of the Republican Guard who were unhappy with their living conditions.
A presidential source said on Sunday that Kabila was not in the residence when the attack happened and that he was safe.
Kabila came to power when his father was assassinated in 2001. He faces presidential and parliamentary elections in November this year, the second such polls since the official end of the 1998-2003 war.
In a controversial Jan. 15 move, parliament backed proposals by Kabila to reduce the presidential vote to a single round, getting rid of the possibility of a run-off between the two leading candidates if neither has an absolute majority.
The change means the winner can claim the presidency with less than 50 percent of popular support. That is seen boosting Kabila's chances of victory because of the fragmented state of the opposition. (Reporting by Jonny Hogg; Writing by Mark John; Editing by Louise Ireland)
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