Invalid latex code when specifying a Markdown image width

I'm having trouble changing the widht of images in Markdown when generating PDFs.

I'm using the example from http://pandoc.org/README.html#pandocs-markdown:

![](cat1.jpg){ width=50% }

The latex output generated by Pandoc look like this:

\includegraphics{cat1.jpg}\{ width=50\% \}

OS: Windows 7 Command line: pandoc document.md --standalone --latex-engine=xelatex document.pdf

pandoc.exe 1.15.0.6
Compiled with texmath 0.8.2.2, highlighting-kate 0.6.
Syntax highlighting is supported for the following languages:
    abc, actionscript, ada, agda, apache, asn1, asp, awk, bash, bibtex, boo, c,
    changelog, clojure, cmake, coffee, coldfusion, commonlisp, cpp, cs, css,
    curry, d, diff, djangotemplate, dockerfile, dot, doxygen, doxygenlua, dtd,
    eiffel, email, erlang, fasm, fortran, fsharp, gcc, glsl, gnuassembler, go,
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    yacc, yaml, zsh

jgm / pandoc

Invalid latex code when specifying a Markdown image width #2803