Unknown gunmen have kidnapped the mother of a local MP in Nigeria's oil-rich Niger Delta, authorities say.
Delta militants have carried out a series of attacks and abductions
The woman was abducted on Monday night from her home in Brass, a coastal village in Bayelsa, one of Nigeria's main oil-producing states.
Meanwhile, the 11-year-old son of another member Bayelsa State House of Assembly has been freed.
In the main Delta city, Port Harcourt, police have arrested a local politician following deadly gang clashes.
Posters of Amakiri Otelemagba were found in a car allegedly used by gunmen in last week's clashes, in which at least 15 people were killed - mostly bystanders.
The city is now calm but BBC Nigeria correspondent Alex Last says given the scale and spread of the fighting, there is a suspicion that powerful political figures may also have been involved in the violence.
He says that in the past, the gangs have been used to rig elections.
It is not clear whether any ransom was paid for the release of the 11-year-old boy. Such payments are always officially denied.
The elderly mother of the speaker of the Bayelsa State legislature was freed on 3 August after 10 days in captivity.
These latest kidnappings are a new trend in the region where militants used to kidnap mostly foreign oil workers for ransom.
In Port Harcourt in neighbouring Rivers State, two toddlers were kidnapped last month.
A three-year-old daughter of a British worker was kidnapped and later released.
Another two-year-old son of a local chief was also snatched on his way to school in Nigeria's violent oil capital and later released to his father.
Foreign oil workers are still being targeted, with at least five still in captivity.
Over 200 expatriate workers have been kidnapped since early 2006 when militant groups stepped up their violent campaign for Niger Delta residents to have a larger share of Nigeria's oil money.
Hostages are normally released unharmed after ransom payments that are often denied by governments and the oil companies involved.
The relationship between the oil militants and the criminal gangs is unclear.