With a portrait of their daughter Megumi Yokota, left, abducted by North Korea in 1978, Shigeru Yokota and his wife Sakie stage a sit-in protest outside Parliamentary buildings in Tokyo Friday

Relatives of Japanese abducted by North Korean agents are holding a three-day sit-in near the prime minister's office in the Japanese capital. The relatives say their patience has run out as they wait for action from both the Japanese and North Korean governments.

Holding placards in one hand and handkerchiefs in the other to wipe their brows as temperatures soared above 30 degrees Celsius, relatives of abductees on Friday began a vigil outside the official residence of Prime Minister Junichiro Koizumi.

Many of the more than 100 relatives and their supporters say they do not believe Pyongyang's assertion that eight of the 13 Japanese North Korea has admitted abducting during the 1970s and '80s are dead. The five others were allowed to return to Japan in 2002.

North Korea snatched the Japanese from coastal communities and used them to teach spies about Japan's language and culture.

Fumiko Hirano's sister is one of the abductees North Korea says is dead.

Ms. Hirano pleads for Prime Minister Koizumi to listen to the voices of those still missing.

Sakie Yokota's daughter was abducted in 1977 when she was 13. Pyongyang claims she committed suicide 12 years ago.

Mrs. Yokota says Prime Minister Koizumi should direct his anger toward North Korea and immediately impose economic sanctions on Pyongyang.

Five million Japanese have signed a petition calling for sanctions.

Prime Minister Koizumi, however, has preferred dialogue to sanctions. The Stalinist North has said it would consider sanctions tantamount to a declaration of war.

Mr. Koizumi on Friday again rebuffed calls for sanctions but said he understands the pain of the families.

The prime minister says before such drastic action as sanctions is taken there is a need to evaluate how effective they would be.

Japan is one of North Korea's few legitimate trade links with the outside world, but some analysts say sanctions would not really hurt Pyongyang because it could ship goods through China.

Mr. Koizumi has made two trips to Pyongyang to meet North Korean leader Kim Jong Il. The first visit, in 2002, secured the release of the five abductees.

Japan is one of the nations participating in the stalled six-party talks about North Korea's nuclear weapons programs.

In talks this week in the South Korean capital, Seoul failed to convince Pyongyang to return to the international discussions on dismantling in nuclear arms program.