Supporters of a jailed critic of the Swaziland government say he has been put in solitary confinement.

Tanele Maseko, the wife of jailed lawyer Thulani Maseko, said Tuesday that the new restrictions followed the online dissemination of a letter in which the inmate describes tough conditions in prison on the first anniversary of his incarceration.

Sibusiso Nhlabatsi, one of Maseko's colleagues, says prison authorities told him the solitary confinement started late last week and will continue for a total of three weeks.

Maseko and Bheki Makhubu, editor of Swaziland's The Nation magazine, were found guilty of contempt of court for publishing articles lamenting alleged threats to judicial independence in the southern African kingdom. They are expected to be released in July.