Arlington Independent School District's superintendent resigned Monday after officials began looking into whether he had violated state laws dealing with the acceptance of honorariums from nonprofits that do business with the district.

Hector Montenegro

The district's Board of Trustees voted unanimously to accept Hector Montenegro's resignation after meeting behind closed doors with their lawyers Monday night.

Board President Jim Ash said Mr. Montenegro will remain on paid administrative leave through July 31.

"This board has not and will not approve a buyout of Mr. Montenegro's contract," Mr. Ash said after the meeting.

Mr. Montenegro started work as superintendent in February. In late June, trustees asked him to produce documentation of his travel and other expenses, as well as explain the extent of his relationship with groups outside the district.

Trustees had voted unanimously last week to place Mr. Montenegro on paid administrative leave during its review of the superintendent's compliance with district and state laws regarding honorariums and travel expenses.

Mr. Montenegro declined to comment. He wasn't present at Monday's meeting.

Previously, he had offered his "deepest apologies" to the board if he used poor judgment, misspoke or wasn't thorough enough in his communications with the board.

Mr. Ash said the superintendent would have to reimburse the district for his outstanding travel expenses.

In return for his resignation, the board will suspend its investigation.

Mr. Montenegro's resignation saddened some Hispanic activists who had stood by him after the controversy surfaced.

"I think at the end of the day, the real losers are our kids," said Luis Castillo, president of the Education Committee of the Arlington chapter of the League of United Latin American Citizens. "He had a track record of turning around low-performing schools, and we were looking up to him to make changes, and he was."