HARARE, Zimbabwe — Zimbabwe’s first lady, Grace Mugabe, accused of attacking and injuring a young model she had found with her sons in a hotel room in South Africa, is seeking diplomatic immunity to fend off an assault charge, South African officials said on Wednesday.

The model, Gabriella Engels, 20, of South Africa, said Mrs. Mugabe, 52, burst into the room and assaulted her with an extension cord on Sunday after finding her at the luxury hotel in Johannesburg with Robert Mugabe Jr., 25, and Chatunga Mugabe, 21.

“There was blood everywhere,” Ms. Engels told the South African broadcaster News24 about the alleged attack by Mrs. Mugabe, the wife of President Robert Mugabe.

“When Grace entered, I had no idea who she was,” Ms. Engels said, adding: “She walked in with an extension cord and just started beating me with it. She flipped and just kept beating me with the plug. Over and over. I had no idea what was going on. I was surprised. I needed to crawl out of the room before I could run away.”