Four people, including two Thais, have been arrested in Laos in an apparent “pattern of religious oppression,” according to a religious rights group. The four were held in the northern province of Luang Namtha for “explaining the Bible to a Lao man in the home of a local Christian,” Christian Solidarity Worldwide (CSW) said on Friday. They have not been charged, CSW said, but were taken to the provincial prison. It is normal practice in Laos to hold suspects at a village or district prison while investigations are carried out. Thai officials have made no comment and it is not clear whether the Thai embassy in Vientiane has intervened. The arrested Thais, both Christians, were Jonasa Wiwatdamrong, 54, and his brother Phnathakorn, 40, said Sirikoon Prasertsee, director of the US-based Human Rights Watch for Lao Religious Freedom. Police found CDs and a picture book of Bible stories in their bags, he told the US Christian news agency Worthy News. This incident is the latest in a recent series of similar cases in Laos in which Christians have been targeted for expressing their religious beliefs, according to CSW. On June 6, a pastor named Asa, 53, was held in the same province and remains in detention. CSW said that two years ago he was forced to sing a pledge that he would not preach Christianity. In March, six Thai Christians were held in Luang Namtha for proselytizing. They were released after paying fines. Christians in at least 15 villages in the province have reported harassment by the authorities, CSW said. “The harassment and detention … is unacceptable,” said CSW’s executive director, Mervyn Thomas. “CSW calls for the immediate release of the Thai and Lao citizens and urges the Lao authorities to adhere to international standards of religious freedom.” Related reports Lao Christians 'facing starvation'