Twenty-eight members of the banned Muslim Brotherhood were arrested in Egypt over the weekend, ahead of Tuesday's key local elections. They were accused of belonging to a banned group and possessing anti-government literature. The pre-dawn raids were the latest in a series of arrests of Brotherhood members, which critics say are part of the ruling party's efforts to limit the Brotherhood's gains in the elections. Those arrested on Saturday included two would-be candidates in Tuesday's poll. Egyptian security forces have arrested more than 600 Brotherhood members since December. The Islamist movement was officially banned in 1954, but the government and the ruling National Democratic Party tolerate it to some extent. "These arrests are a typical practice in the Egyptian system," Usama Harb, president of the opposition Democratic Front Party, told The Media Line. "The Muslim Brotherhood is the biggest and most important opposition group in the country, so the government is interested in containing and controlling it." Harb said the National Democratic Party was trying to eliminate all other forces from the competition to monopolize the elections. The Interior Ministry insists the arrests are not politically motivated. The ministry said all the arrest warrants came with an explanation of the reasons for the detention. The Brotherhood fielded candidates as independents in the 2005 legislative elections and gained a fifth of the seats in the lower house of parliament. The United States is closely following events in Egypt. The White House has expressed concern about the arrests and called on the Egyptian government to stop any actions that would compromise the ability of the Egyptian people to participate in a free and fair election. Egypt has an interest in falling in line with the US's wishes, since it gets an annual $1.4 billion in aid from Washington. The municipal elections have gained importance because of a constitutional amendment that requires independent presidential candidates to have the backing of municipal councilors. Meanwhile, Egyptian security forces are pursuing two Sudanese men suspected of planning a terrorist attack at a resort in Sinai. It is assumed they entered Egypt through the Sudanese-Egyptian border and they are believed to be driving a small truck laden with explosives.