A teacher smiled in her mugshot after being arrested on suspicion of sexual activity with a 17-year-old student.

Sarah Fowlkes, 27, faces up to 20 years in prison if she is convicted of the crime.

She has also been suspended from her job at Lockhart High School in Texas.

Despite this, the biology teacher grinned from ear-to-ear after she had her mugshot taken hours after celebrating her birthday with her husband.

Local police obtained an arrest warrant for Mrs Fowlkes, who turned herself in.

Police claim to have found evidence of messages sent between her and the student.

They said "the content was sexual in nature".