diff --git a/block.go b/block.go
index e73cf02..2069163 100644
--- a/block.go
+++ b/block.go
@@ -196,6 +196,7 @@ func (p *parser) prefixHeader(out *bytes.Buffer, data []byte) int {
 		if j < end && k < end {
 			id = string(data[j+2:k])
 			end = j
+			skip = k + 1
 		}
 	}
 	for end > 0 && data[end-1] == '#' {
diff --git a/block_test.go b/block_test.go
index 20f29a1..fc03836 100644
--- a/block_test.go
+++ b/block_test.go
@@ -191,6 +191,12 @@ func TestPrefixHeaderIdExtension(t *testing.T) {
 		"# Header 1 {#someid\n",
 		"<h1>Header 1 {#someid</h1>\n",
 
+		"# Header 1 {#someid\n",
+		"<h1>Header 1 {#someid</h1>\n",
+
+		"# Header 1 {#someid}}\n",
+		"<h1 id=\"someid\">Header 1</h1>\n\n<p>}</p>\n",
+
 		"## Header 2 {#someid}\n",
 		"<h2 id=\"someid\">Header 2</h2>\n",