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A nonstatic and circularly symmetric exact solution of the Einstein equations(with a cosmological constant $\Lambda$ and null fluid) in $2+1$ dimensions isgiven. This is a nonstatic generalization of the uncharged spinless BTZ metric.For $\Lambda = 0 $, the spacetime is though not flat, the Kretschmann invariantvanishes. The energy, momentum, and power output for this metric are obtained.Further a static and circularly symmetric exact solution of theEinstein-massless scalar equations is given, which has a curvature singularityat $r =0$ and the scalar field diverges at $r=0$ as well as at infinity .Comment: 8 pages, Latex, no numbe

Exact solutions of Einstein and Einstein-scalar equations in 2 + 1 dimensions