In this 42 U.S.C. § 1983 action, Aaron Olson appeals after the district court 1 dismissed his second amended complaint, ■with prejudice, and denied him leave to amend his complaint further.

Upon careful review, we agree with the district court that Olson’s claims were barred by res judicata, see Laase v. Cty. of Isanti, 638 F.3d 853, 856 (8th Cir. 2011) (de novo review of dismissal based on res judicata); Ripplin Shoals Land Co. v. U.S. Army Corps of Eng’rs, 440 F.3d 1038, 1042 (8th Cir. 2006) (discussing application of doctrine of res judicata), and that, in any event, his complaint failed to state a claim, see Stone v. Harry, 364 F.3d 912, 914 (8th Cir. 2004) (pro se complaints must be liberally construed, but they must still contain sufficient facts to support claims advanced; de novo review of dismissal based on insufficient factual allegations to support claims advanced). We further conclude that the district court acted within *606 its discretion in denying Olson leave to amend his complaint further. See Joshi v. St. Luke’s Hosp., Inc., 441 F.3d 552, 555, 557-58 (8th Cir. 2006) (reviewing denial of motion to amend complaint for abuse- of discretion; reviewing de novo underlying legal conclusion as to whether proposed amendment would have been futile; district court may deny leave to amend if amendment would be futile).

Accordingly, we affirm. See 8th Cir. R. 47B.