Cannot find BLAS on a machine with MKL when installing scipy via pip

I installed Intel MKL and other libraries for a customized numpy. Here is my `~/.numpy-site.cfg`:

    [DEFAULT]
    library_dirs = /usr/lib:/usr/local/lib
    include_dirs = /usr/include:/usr/local/include
    
    [mkl]
    library_dirs = /opt/intel/mkl/lib/intel64/
    include_dirs = /opt/intel/mkl/include/
    mkl_libs = mkl_intel_ilp64, mkl_intel_thread, mkl_core, mkl_rt
    lapack_libs =
    
    [amd]
    amd_libs = amd
    
    [umfpack]
    umfpack_libs = umfpack
    
    [djbfft]
    include_dirs = /usr/local/djbfft/include
    library_dirs = /usr/local/djbfft/lib

This configuration file seems OK during the installation of numpy. But when I was installing scipy via `pip3 install scipy`, it reported that

    numpy.distutils.system_info.BlasNotFoundError:
    
        Blas (http://www.netlib.org/blas/) libraries not found.
    
        Directories to search for the libraries can be specified in the
    
        numpy/distutils/site.cfg file (section [blas]) or by setting
    
        the BLAS environment variable.

In my mind MKL is an implementation of Blas so just mentioning MKL should be fine. I've tried

 1. `export LD_LIBRARY_PATH=/opt/intel/mkl/lib/intel64:$LD_LIBRARY_PATH‌​`

 2. `export BLAS=/opt/intel/mkl/lib/intel64`

 3. Copy the content in the `[mkl]` section and paste into the `[blas]` section in the file `~/.numpy-site.cfg`

But none of these works. So what is going wrong? Does scipy respect `~/.numpy-site.cfg`? Thank you.