President Barack Obama is expected to arrive in Dallas to pay tribute to the five police officers who were shot and killed during a deadly sniper attack.
Mr Obama will deliver remarks at a memorial service for the slain officers, who were killed last week at a Dallas protest.
The gunman was killed by a bomb delivered by a police robot during a standoff with authorities.
According to BBC Mr Obama’s trip comes amid mounting racial tension across the country.
Micah Xavier Johnson, 25, opened fire at a protest held over the recent police shootings of Philando Castile in Minnesota and Alton Sterling in Louisiana. He killed five policemen and wounded at least nine other officers and two civilians.
The Army veteran told police negotiators he was upset by recent shootings and wanted to kill white people, specifically officers.
First Lady Michelle Obama, Vice President Joe Biden and his wife, Jill, will also meet privately with the families of the victims on Wednesday.
“The president is hoping to offer some measure of comfort,” White House spokesman Josh Earnest said.
President George Bush and First Lady Laura Bush are also expected to attend the interfaith service.
Mr Bush, who settled in Dallas after leaving office in 2009, is to schedule to speak at the service as well.
Dallas police have ramped up security ahead of the president’s visit, enlisting help from the Arlington Police Department to work with Secret Security.