HOUSTON — A Houston insurance agent indicted on charges she bilked nearly a dozen clients out of more than $3 million in an annuity scam has accepted a 20-year prison term in a plea deal.

The Harris County District Attorney’s Office said Monday investigators determined Celia Castillo set up a bank account where she diverted investments from clients who thought they were buying annuities ensuring them regular annual payments. Instead, the money went to Castillo’s own account and no annuities were bought.

Texas Department of Insurance investigators say Castillo singled out clients who were older and had no nearby relatives. Her victims all were well over age 70 and two were more than 90.

Investigators began looking into her activities after getting complaints about the legitimacy of investment products she was selling.