Race conditition when using Process RedirectStandardError and RedirectStandardOutput,

            if(!p.WaitForExit(mstimeout))
            {
                p.Kill();
            }

        finally
        {
            p.OutputDataReceived -= OutputDataReceived;
            p.ErrorDataReceived -= ErrorDataReceived;
            p.Dispose();
            p = null;
            GC.Collect(GC.MaxGeneration, GCCollectionMode.Forced, blocking: true);
        }

    private string execute(string command, string arguments, int mstimeout)
    {
        bool timeout = false;
        string report = string.Empty;
        StringBuilder output = new StringBuilder();
        StringBuilder error = new StringBuilder();
        Process p = new Process();
        DataReceivedEventHandler StoreError = (o, e) => { error.Append(e.Data); };
        DataReceivedEventHandler StoreOutput = (o, e) => { output.Append(e.Data); };
        try
        {
            Debug.WriteLine(command);
            Debug.WriteLine(arguments);
            p.StartInfo.FileName = command;
            p.StartInfo.Arguments = arguments;
            p.EnableRaisingEvents = true;
            p.StartInfo.CreateNoWindow = true;
            p.StartInfo.UseShellExecute = false;
            p.StartInfo.RedirectStandardError = true;
            p.StartInfo.RedirectStandardOutput = true;
            p.OutputDataReceived += StoreOutput;
            p.ErrorDataReceived += StoreError;
            p.Start();
            p.BeginErrorReadLine();
            p.BeginOutputReadLine();
            if (!p.WaitForExit(mstimeout))
            {
                p.Kill();
                timeout = true;
                Debug.WriteLine("Process killed");

            }
            else
            {
                p.WaitForExit();
            }
        }
        finally
        {
            report = output.ToString() + "\n" + error.ToString();
            Debug.WriteLine(report);
            p.Dispose();
        }
        if (timeout)
        {
            throw new TimeoutException("Timeout during call: " + command + " " + arguments);
        }
        return report;
    }