According to relatives, the Minnesota residents went missing in early January in Savannakhet province on their way to a funeral.
The State Department says the U.S. Embassy in Vientiane (vee-en-TEE-an) has contacted the Lao government for further information.
Three bodies were recently found in a burned van in the province, and Khammanh Kongdaravong (kam-MAHN kong-DAH-rah-wong) said relatives in Laos have identified her husband, Souli (SOO-lee), as one of the dead.
The circumstances of the fire are unclear.
The other missing men are Bounthieng Insixiengmai (boon-TEE-eng IN-shee-eng-my) and Bounma Phannhotha (BOON-mah pan-HO-tah).
Laos is currently facing international pressure over the unrelated disappearance of a prominent Lao social activist, Sombath Somphone (som-BAT som-PON).