TRIPOLI — Prime Minister Ali Zidan of Libya said on Friday that his kidnapping the day before by militia members was no different than a “coup” and had been orchestrated by opponents in the legislature who want to force him from office. Scores of armed gunmen seized Zidan from his hotel room in Tripoli early Thursday and released him nine hours later only under pressure from Defense Ministry officials and rival militias. Zidan, a former diplomat and human rights lawyer who has headed Libya's interim government since last October, was unharmed, but the abduction underlined the weakness of his government against the militias. In a televised news conference on Friday, Zidan accused political opponents of trying to “overthrow the government.” “This was not an attempted kidnapping only of a prime minister, but of the government,” he said, news agencies reported. Zidan has struggled with the militias and their leaders for months. The government's efforts to push through reforms of the army and police forces and absorb the militias into state institutions has met with resistance from militia members, many of them veterans of the uprising against Col. Muammar Gaddafi, the longtime dictator. Their leaders complain that they have been excluded from Parliament and government decision-making and left out of discussions on the future of Libya, in particular overhauls to the country's security sector. Armed groups frequently burst into government offices to register their complaints about unpaid salaries or bills. In May, militiamen besieged parliament and a ministry building demanding the passing of a law against members of the Gaddafi government and calling for the government's resignation. After his release Zidan called for wisdom to mend fences. But on Friday he appeared ready to confront those behind his abduction. He accused members of parliament of plotting to remove him and using the militias for their political goals. He said the armed men who abducted him told him they belonged to the Revolutionaries Operations Room, a security agency that was recently created out of several militias by Nouri Abusahmain, the head of the parliament, known as the General National Congress, as a security force for the capital. But the prime minister said Abusahmain, who visited him while he was held, was not involved, and he thanked him for his help in ensuring his freedom. — Agencies