SAN SALVADOR (Reuters) - El Salvador's former President Antonio Saca was arrested Saturday on corruption charges alleging misuse of public funds, the attorney general's office said on Sunday.

Saca, a businessman who ruled the small Central American national from 2004 to 2009, was detained Saturday night during the wedding reception of one of his sons at a reception hall in the capital.

He was arrested along with high-ranking former officials of his government, including ex-communications minister Julio Rank and youth minister Cesar Funes.

Several hours after the initial arrests, Saca's former private secretary Elmer Charlaix voluntarily surrendered to the police. He faces charges of embezzling at least $18 million.

In addition to Saca, a total of six other suspects have been arrested, the attorney general's office added in a post on Twitter.

In March, El Salvador's supreme court ordered a civil trial of the former president, as well as his wife, Ana Ligia de Saca, because he could not explain how he acquired $5 million at the end of his term.

Saca, who also had his bank accounts and properties frozen, was expelled from his political party, the conservative Nationalist Republican Party (Arena), in 2009 due to the alleged irregularities.

In February, former president Mauricio Funes was also ordered to stand trial for more than $700,000 that he was not able to account for following his 2009-2014 term.

Funes, a former TV journalist, was leader of the leftist political party Farabundo Marti National Liberation Front.

In January, another ex-president of El Salvador and Arena leader, Francisco Flores, died after suffering a stroke as he waited to face trial over embezzlement charges.

(Reporting by Nelson Renteria; Writing by David Alire Garcia; Editing by Nick Zieminski)