A bomb blast on a bus in Volgograd, Russia has killed at least six people and injured 20, according to reports in Russia.
More top news
A top temperature today of 13 Celsius (55F).
Mr Trump tweeted that Mr McMaster has done "an outstanding job & will always remain my friend." He said MrBolton will take over on April 9.
The committee wants a more stringent interpretation of air quality laws and for noise estimates to reflect a range of possible flight paths.