Cambodian police have arrested eight people for painting messages on their rooftops asking U.S. President Barack Obama to help them avoid eviction.

Activists say over 180 families living on the perimeter of Phnom Penh airport have been told to vacate their houses because of security concerns ahead of President Obama's visit to Cambodia on Monday. They say they have not been offered proper compensation.

Some of the families plastered pictures of Mr. Obama on their houses next to the spray-painted message “SOS.” Rights activists say police raided the homes early Thursday and ordered the artwork removed, arresting those responsible.

Forced evictions are common in Cambodia, where few people have land titles – a lingering result of the Khmer Rouge's abolition of private property during the 1970s. The evictions have displaced thousands and resulted in frequent violent clashes with security forces.

Rights groups have urged Mr. Obama to prominently raise human rights concerns next week when he becomes the first U.S. president to visit the southeast Asian country.

President Obama is attending the ASEAN and East Asia summits in Phnom Penh next Monday. He is also traveling to Burma and Thailand as part of his visit, the first foreign trip since his re-election.

Cambodian opposition leader Sam Rainsy last month urged Mr. Obama to cancel his visit to Cambodia on the grounds that it would provide legitimacy to the rule of Prime Minister Hun Sen, who has been in power for 27 years.

New York-based Human Rights Watch said this week that the visit will provide a unique opportunity for the U.S. to call for an end to longstanding human rights abuses, including alleged extrajudicial killings, torture, and abductions.