The University of Houston went into pandemonium this afternoon when a pregnant Beyoncé showed up to surprise her mother Tina Knowles during the latter's interview for the Living Archives of the school women's studies collection.

Even U of H's administration had no idea Beyonce was going to show up, but the singer stood over the balcony of the M.D. Anderson Library's Rockwell Room, waving at students and guests. Library administration member Carolyn Meanley, who helped plan the event, was also unaware of the surprise appearance.

"It was literally pandemonium when word got out that she was here," Meanley said. "We had to lock the office door because the students were figuring out ways to enter the Rockwell room to get to her," she added with an excited smile.

When the news hit Twitter, both "Beyonce" and "U of H" were among the social network's top trending topics. About 200 people filled the Rockwell Room, including students, alumni, administration and media. Tina Knowles had several other family members come to UH to support her presentation, including cousins and a brother and sister-in-law.

"Since Beyoncé is pregnant, she isn't performing," added Meanley. "She's relaxing and enjoying time with family."

After telling her story of branding a fashion line - House of Dereon, from which several articles were on display - and being the mother of one of the most entertaining women of the past two decades, Tina Knowles was interviewed by communication students and members of the media.

The Living Archives are a collection of papers and life stories of Houston women and female-founded local organization that have successfully made a mark in history. Other women honored the collection are current Houston Mayor Annise Parker and former Mayor Kathy Whitmire.