The Standard & Poor's 500 index ended pretty much where it started the day on Friday, at 1,955 points, down a fraction of a point.
The Dow Jones industrial average lost 50 points, or 0.3 per cent, to 16,662. It was down 138 earlier.
The Nasdaq composite rose 11 points, or 0.3 per cent, to 4,463.
The Ukrainian president said his military destroyed most of a Russian military convoy that entered his country. Russia denied it.
Bond prices soared, sending the yield on the 10-year Treasury to its lowest of the year.
In late trading the yield was 2.34 per cent, from 2.40 per cent late Thursday. It went as low as 2.30 per cent.