Where are they hiding ?

Number Theory Level 3

$012345678910{\color{#3D99F6}111}21314\ldots$

The above is the beginning of all non-negative integers concatenated into a single infinite string.

$\color{#3D99F6}111$ is the first sub-string with 3 identical digits in a row, with different digits preceding and following the run of the identical digits. The first $\color{#3D99F6}1$ of $\color{#3D99F6}111$ comes at position 13 (from left) in the infinite string.

Where is the first such sub-string with 4 identical digits?

Give the position of the first digit of the four.