KINGSTON, Ont. - A woman accused of killing her three daughters and her husband's other wife admitted in court today that she lied to police.

Tooba Yahya, 42, testified that she lied in her post-arrest interrogation, saying she was under pressure and "it was all lies."

Yahya told that officer that she was at the scene the night the four people died and heard the car splash into the water, but she said today that she made it up because she was under pressure.

She admitted under cross-examination that she is under pressure on the stand today, but says she's not lying now.

It's alleged that Shafia sisters Zainab, 19, Sahar, 17 and Geeti, 13, along with Shafia's first wife in a polygamous marriage were killed over family honour.

Their bodies were found June 30, 2009, in a car at the bottom of a canal in Kingston, when the Montreal family was on their way home from a trip to Niagara Falls, Ont.

Yahya, her husband Mohammad Shafia, 58, and son Hamed, 21, have each pleaded not guilty to four counts of first-degree murder.