ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH Police officers pay their respects ahead of the funeral for Officer Lorne Ahrens in Plano, Texas, U.S. July 13, 2016. Five officers, including Ahrens, were killed in a shooting incident in Dallas July 7. REUTERS/Carlo Allegri TEMPLATE OUT. - RTSHRQA

Police officers pay their respects ahead of the funeral for Officer Lorne Ahrens in Plano, Texas, U.S. July 13, 2016. Five officers, including Ahrens, were killed in a shooting incident in Dallas July 7. REUTERS/Carlo Allegri - RTSHRNS

Katrina Aherns sits with son Magnus Aherns during the funeral of her husband, slain Dallas police officer Lorne Ahrens following the multiple police shootings in Dallas, Texas, U.S., July 13, 2016. REUTERS/Carlo Allegri TPX IMAGES OF THE DAY - RTSHSZV

A horse drawn carriage pulls the casket of slain Dallas police officer Lorne Aherns following the multiple police shootings in Dallas, Texas, U.S., July 13, 2016. REUTERS/Carlo Allegri - RTSHT59

A police officer pays his respects ahead of the funeral for Officer Lorne Ahrens in Plano, Texas, U.S. July 13, 2016. Five officers, including Ahrens, were killed in a shooting incident in Dallas July 7. REUTERS/Carlo Allegri - RTSHQYS

Onlookers watch as first responders salute while the hearse carrying the body of Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, drives by during a funeral procession in Dallas, Texas, U.S. July 13, 2016. REUTERS/Brandon Wade - RTSHSML

Magnus Ahrens drops a flower into the grave of his father, Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, after the burial ceremony at Restland Public Safety Memorial Gardens in Dallas, Texas, U.S. July 13, 2016. REUTERS/Cooper Neill TPX IMAGES OF THE DAY - RTSHT4D

Magnus Ahrens carries a folded U.S. flag after the burial ceremony for his father, Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, at Restland Public Safety Memorial Gardens in Dallas, Texas, U.S. July 13, 2016. REUTERS/Cooper Neill - RTSHT73

Police officers pay their respects ahead of the funeral for Officer Lorne Ahrens in Plano, Texas, U.S. July 13, 2016. Five officers, including Ahrens, were killed in a shooting incident in Dallas July 7. REUTERS/Carlo Allegri - RTSHR6T

First responders salute as the hearse carrying the body of Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, drives by during a funeral procession in Dallas, Texas, U.S. July 13, 2016. REUTERS/Brandon Wade - RTSHSMI

A funeral procession for slain Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, is pictured in Dallas, Texas, U.S. July 13, 2016. REUTERS/Rex Curry - RTSHSWT

Katrina sits with son Magnus during the burial ceremony of her husband, Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, at Restland Public Safety Memorial Gardens in Dallas, Texas, U.S. July 13, 2016. REUTERS/Cooper Neill - RTSHT7K

A mourner cries during the funeral for Officer Lorne Ahrens in Plano, Texas, U.S. July 13, 2016. Five officers, including Ahrens, were killed in a shooting incident in Dallas July 7. REUTERS/Carlo Allegri - RTSHRZE

Onlookers watch as the hearse carrying the body of Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, drives by during a funeral procession in Dallas, Texas, U.S. July 13, 2016. REUTERS/Brandon Wade - RTSHSMU

Officers leave the burial ceremony of Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, at Restland Public Safety Memorial Gardens in Dallas, Texas, U.S. July 13, 2016. REUTERS/Cooper Neill - RTSHT6R

Plano Police Offier Greg Carey salutes the funeral procession of Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, in Dallas, Texas, U.S. July 13, 2016. REUTERS/Rex Curry - RTSHSU0

Katrina Ahrens, wife of Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, picks flowers to place at his gravesite at Restland Public Safety Memorial Gardens in Dallas, Texas, U.S. July 13, 2016. REUTERS/Cooper Neill - RTSHT6B

Dallas police officer Eddie Coffey reacts while speaking at the funeral for Officer Lorne Ahrens in Plano, Texas, U.S. July 13, 2016. Five officers, including Ahrens, were killed in a shooting incident in Dallas July 7. REUTERS/Carlo Allegri - RTSHSB7

The hearse carrying the body of Dallas Police Department Senior Corporal Lorne B. Ahrens, who was among five police officers shot dead the previous week, enters Restland Memorial Park in Dallas, Texas, U.S. July 13, 2016. REUTERS/Brandon Wade - RTSHSM0

A horse drawn carriage pulls the casket of slain Dallas police officer Lorne Aherns following the multiple police shootings in Dallas, Texas, U.S., July 13, 2016. REUTERS/Carlo Allegri - RTSHT4P