Graham Dwyer's murder trial has heard his work phone can't be traced between 5 and 9pm on the evening of Elaine O'Hara's alleged murder.

However there is evidence a text message 'go down to shore and wait' was sent at 6pm, between the phones the pair are alleged to have secretly used.

The jury heard evidence the message appeared to have been sent while the phone was in the Shankill area.

The two phones in question were later found in Vartry reservoir.

The architect of Kerrymount Close, Foxrock denies stabbing 36 year old Elaine O'Hara at Killakee mountain on August 22nd.

She was last seen near Shanganagh cemetery before 6pm on that date.

Judge Tony Hunt has warned the jury some of the evidence it'll hear this afternoon will be difficult.